Authentic Leadership and Task Performance in Public Organizations from Sustainability Perspective: The Mediating Role of Supportive Organizational Culture

Abstract

This study aims to examine the effect of authentic leadership on task performance in public organizations from sustainability perspective and to test whether supportive organizational culture plays a mediating role in this relationship. A quantitative, correlational, cross-sectional survey design was used for this study. A questionnaire form was used to collect data. Authentic leadership, task performance, and supportive organizational culture were measured using standard scales. After scale adaptation and factor analyses, one authentic leadership item was removed, resulting in a 15-item structure. Data were collected via Google Forms from 452 civil servants and contracted employees working in a metropolitan municipality in Turkey using convenience sampling. The data were analyzed using SPSS 26.0 and AMOS 22 for CFA. Construct validity was established through exploratory and confirmatory factor analyses (EFA and CFA). Internal consistency coefficients were found to be high. Common method bias was assessed using Harman’s single-factor test. Hypotheses were tested using PROCESS Macro Model 4 with 5000 bootstrap resamples. The findings indicate that authentic leadership does not have a significant direct effect on task performance. However, authentic leadership significantly and positively predicts supportive organizational culture, and supportive organizational culture significantly enhances task performance. Moreover, the effect of authentic leadership on task performance occurs indirectly through supportive organizational culture, indicating a full mediating role. The results suggest that, in public organizations, leadership effects are more likely to be transferred into performance outcomes when it is embedded in cultural norms and supportive practices. From a sustainability perspective, in the absence of direct measures of sustainability outcomes, self-reported task performance is interpreted as a proximal organizational outcome rather than a direct indicator of sustainability. Therefore, the study offers theoretically grounded sustainability implications for institutional continuity via supportive organizational culture, efficiency in the use of resources and service quality with the practices of green HR in the public sector. Future research should employ multi-source and multi-indicator measures of sustainability.

1. Introduction

For business organizations to survive and succeed in a competitive environment, they require well-qualified employees to allocate resources effectively and to pursue sustainable policies and strategies. To be able to use resources effectively, to maintain employees with high competencies, and to pursue sustainable policies can only be achieved by an effective modern leadership approach.

Among the leadership styles that have attracted considerable attention in recent years, authentic leadership stands out as one of the most important approaches supporting sustainability policies and encouraging employees’ development and motivation by giving priority to achievement, building trust, and ethical values. Authentic leaders are distinctive not only for developing both employees and the organization, but also for valuing environmentally sensitive ethical principles and policies.

In this process of leading employees toward success in such a dynamic environment that the organization operates, organizational culture plays a critical role. A supportive organizational culture—characterized by allowing qualified employees to participate in management, ensuring transparent and open communication, fostering teamwork and trust-based relationships, strengthening employees’ sense of belongingness, and enabling empowerment—can reinforce the practices of authentic leaders and can also enhance employees’ task performance.

When a supportive organizational culture is integrated with an authentic leadership style, employees are more likely to feel that they work in an organization that is sensitive and committed to sustainable policies. The organizations that support employee development, and environmentally responsible and resource-efficient strategies may, in turn, generate positive effects on employees’ task performance. Task performance in relation to the fulfillment of expectancies defined by job descriptions ensures the achievement of organizational goals. Employees empowered by an authentic leader may trust their leaders’ ethical values in line with the support of their organizational culture. Accordingly, employees will invest greater effort to deliver a strong task performance.

Organizations that develop their employees’ competencies enable them to demonstrate higher levels of task performance in achieving organizational objectives, and organizations that pursue sustainable practices by upholding ethical values add value to their wider environment.

Building on this rationale, the present study examines, from a sustainability perspective, the role of supportive organizational culture in the relationship between public employees’ perceptions of authentic leadership and task performance. In doing so, sustainability is treated as a conceptual framing relevant to long-term public-service continuity, decent work conditions, and institutional functioning, rather than as a directly measured empirical outcome.

Despite growing interest in authentic leadership in public organizations, research has not fully specified how authentic leadership is converted into employees’ task performance, particularly in settings where bureaucratic routines and formal performance systems may constrain behavioral discretion. Accordingly, this study asks whether supportive organizational culture functions as a key transmission mechanism through which authentic leadership is transferred into task performance in a metropolitan municipality context.

By conceptualizing supportive organizational culture as a cultural transmission mechanism, this study extends authentic leadership research in the public sector and helps clarify why leadership affects task performance in an indirect rather than direct way. Practically, the findings suggest that cultivating supportive norms (e.g., psychological safety, participatory communication, and fair processes) can help transfer ethical and transparent leadership into day-to-day task execution and performance.

The dynamics of the public sector include strict rules and procedures, bureaucracy, and formal task orders. For this inflexible organizational structure to function effectively, managers with ethical, transparent, and reliable characteristics, such as in the case of authentic leadership style, are required to conduct activities through organizational goal achievement. In addition to authentic leadership practices, a supportive organizational culture may enhance task achievements of employees in such a public sector where procedures should be pursued carefully.

In line with this aim, this study examines the effect of authentic leadership on task performance, analyzes the mediating role of supportive organizational culture, and interprets the findings through a contextual sustainability perspective.

2. Literature Background and Hypotheses

2.1. Authentic Leadership

The concept of leadership is as old as human history, and early references to leadership principles can be traced back to Egyptian hieroglyphs and Sun Tzu’s The Art of War, written approximately two thousand five hundred years ago [1]. This book draws attention to such fundamental qualities of leadership as intelligence, trustworthiness, people-orientation, courage, and determination. Today, however, leadership is addressed with more than 350 different definitions due to organizational and societal transformations and offers an increasingly evolving conceptual framework [2]. Despite this diversity in the literature, a universal definition of leadership has not been reached yet [3]. The concepts “lead”, “leader” and “leadership”, which originate from the Anglo-Saxon verb “leaden”, encompass the meanings of guiding and moving forward [4].

One of the approaches that has attracted increasing attention in the field of leadership in recent years is authentic leadership. Regarding leadership behaviors that create an impact on followers, build trust, motivate and encourage them, numerous academic studies have been conducted from past to present within the frameworks of behavioral, contingency and modern leadership approaches. The concept of authentic leadership is derived from the Ancient Greek teaching of “being true to oneself” and refers to the individual’s behaving in accordance with his or her values and true self [5,6,7]. It has gained visibility in the management literature since 1960s, together with developments in the fields of positive psychology, educational science and sociology [6,8]. This approach is based on the leader acting in a transparent, consistent and ethical manner while remaining faithful to his or her own values and beliefs [9,10]. Authentic leaders stand out through their consistent, sincere and genuine behaviors. By clearly expressing their own values and vision, they inspire their followers and enhance their motivation [11]. This leadership style has a structure that recognizes individual differences and focuses on developing employees’ abilities. This model, in which ethical and transformational understandings of leadership are blended, stands out as a solution-oriented paradigm particularly in the 21st century, when crises of trust and ethical violations are frequently experienced [5].

Walumbwa et al. (2008) define authentic leadership through four core components [5]. These components are self-awareness, balanced processing, internalized moral perspective, and relational transparency. Self-awareness refers to the leader’s ability to recognize and evaluate his or her own values, emotions, strengths and weaknesses [12], while balanced processing represents the leader’s ability to evaluate events and situations in an unbiased way and analyze them fairly [10]. Internalized moral perspective ensures that the leader makes decisions in line with internal ethical principles rather than external pressures [11,13] whereas relational transparency means that the leader expresses his or her emotions and intentions to followers in an open, honest and sincere way [14]. These components are of critical importance for understanding how authentic leadership functions at both individual and organizational levels. In the literature, authentic leadership is mostly measured by the 16-item scale developed by Walumbwa et al. (2008) [5].

Authentic leadership, by enabling the leader to build trust through behaving consistently with his or her true self, creates an effect that fosters trust and commitment among employees [7]. Within the framework of social exchange theory, leaders’ fair, supportive and transparent attitudes strengthen the reciprocal trust relationships between them and their employees [15]. This leads employees to approach their work with greater dedication in return for ethical leadership behaviors [14]. Authentic leaders, whose practices are grounded in ethical principles, create a trust-based social exchange process with employees and thereby strengthen their job performance [16].

In the literature, it has been shown that authentic leadership has particularly positive effects on organizational outcomes such as task and contextual performance [17,18]. However, it is stated that this relationship does not occur directly, but rather indirectly through mediating variables such as organizational culture, psychological safety and leader–member relations. Studies that examine the effect of authentic leadership on task performance have revealed that increases in leadership behaviors positively influence employee performance [19,20,21,22,23,24,25]. Yet some studies show that the relationship between authentic leadership and task performance is not always significant and may vary depending on contextual factors [26,27]. On the other hand, it is indicated that authentic leadership develops employees’ positive personal resources (psychological capital) such as hope, psychological resilience, self-efficacy and optimism, and thereby helps create a supportive culture in the organization [28]. Furthermore, this leadership style contributes to employees’ managing work–family balance in a healthier way, thereby increasing overall job satisfaction and performance [29]. Similarly, it has been found that authentic leaders with self-awareness and an ethical stance positively influence employees’ perceptions of leadership, organizational citizenship behavior and contextual performance [18,30]. The fact that this leadership style builds a supportive and trust-based organizational culture increases employees’ sense of psychological safety and leads them to embrace their tasks with higher motivation [6,29].

In order to explain the effect of authentic leadership on task performance, it is of great importance, from both a theoretical and a practical perspective, to carefully examine mediating mechanisms such as supportive organizational culture. Individuals who work with leaders that are committed to ethical principles and act fairly and transparently in their organizations not only fulfill their prescribed tasks, but also support the achievement of organizational goals through discretionary contributions. The fair, transparent, empathetic and supportive attitudes of authentic leaders strengthen the sense of trust among employees and lay the groundwork for the emergence of a collaborative organizational culture [31]. Employees who trust their leaders function as a kind of social capital for the sustainability of the organization. In organizations where trust and a supportive organizational culture prevail, employees display more creative, committed and productive behaviors. Therefore, trust-based leadership practices, in the long term, foster the development of a supportive and ethical organizational culture and contribute to employees’ sustainable performance [32]. In this context, in the public sector, a supportive organizational culture not only creates an environment that meets employees’ psychological needs but also functions as an organizational mediating mechanism that reinforces the effect of authentic leadership on task performance. This cultural structure, which is based on trust, openness and cooperation, ensures that the leader’s ethical, transparent and consistent behaviors have a lasting impact on employees and thus secures the sustainability of leadership at institutional level. Such an organizational culture contributes to employees developing a sincere commitment not only to their individual performance targets but also to the organization’s sustainability vision and its goals of social responsibility. Therefore, supportive culture can be viewed as the organizational mechanism that helps transfer the climate of trust created by authentic leadership into everyday practices and thus strengthens task performance more sustainably over time. Meta-analytic studies indicate that authentic leadership generally shows a positive pattern of associations with performance-related outcomes; however, these effects often operate through specific processes rather than occurring directly. In their cross-cultural meta-analytic review, Zhang et al. (2022) report that authentic leadership is positively associated with employee performance and a range of organizational outcomes, while emphasizing that this relationship is particularly strengthened through intermediate mechanisms such as leader–member exchange (LMX) and job satisfaction [33]. In addition, Hoch et al. (2018) examined authentic leadership alongside ethical and servant leadership and compare these approaches with transformational leadership [34]. They found substantial empirical overlap between authentic and transformational leadership and showed that, for many outcomes, authentic leadership explains only limited “incremental” variance beyond transformational leadership [34]. In other words, rather than assuming that authentic leadership alone is sufficient to count for performance outcomes, a stronger theoretical approach should focus on the mediating mechanisms that transmit leadership effects (e.g., supportive organizational culture) and on contextual boundary conditions such as those characteristics of the public sector. Accordingly, this study analyzed how authentic leadership influences task performance through the mediating role of supportive organizational culture.

2.2. Task Performance

Task performance is a concept that expresses the extent to which individuals fulfill the responsibilities defined within the framework of their job descriptions and is of critical importance for achieving organizational goals [35]. Motowidlo and Kell (2012) defined performance as “the total value to the organization of the behaviors that a person performs over a standard interval of time” [36].

Borman and Motowidlo (1993), who conceptualized performance in two dimensions as task and contextual, associated task performance with the extent to which the employee fulfills the tasks that directly contribute to the technical core of the organization within the scope of his or her job description [37]. Task performance contains behaviors that are carried out on the basis of formal job descriptions, performed in return for pay, and directly contribute to organizational outcomes [37]. Conway (1999) addressed task performance in two subdimensions as technical–administrative and leadership task performance, and stated that, in addition to activities such as planning, organizing, technical knowledge and administrative work, leadership roles such as human relations, guidance, employee motivation and feedback are also included within this scope [38]. Borman and Brush (1993) revealed that leaders’ behaviors such as providing guidance, motivating, offering constructive criticism and conducting performance appraisals are among the important components of task performance [39].

In their studies on task performance, Borman and Motowidlo (1997) drew attention to some fundamental characteristics of task performance [40]. Accordingly, task activities may vary substantially across jobs within the same organization; in line with what is specified on performance appraisal forms. These activities involve behaviors that are more predictable compared to contextual performance. Task activities consist of the behaviors required by the role, and employees receive a certain wage in return for these activities. It is also emphasized that the antecedents of task performance are largely related to employees’ cognitive abilities, knowledge, and skills. These activities contribute directly or indirectly to the technical core of the organization and ensure the sustainability of organization functioning. Studies in the literature also show that task performance is closely associated with these characteristics [40]. In addition, individual factors (e.g., organizational identification, perceived support) and organizational factors (e.g., leader support, development-oriented culture) stand out as important determinants that affect task performance [41,42]. It has been found that employees’ feeling committed and valued by the organization enhances their performance [43], and that leader support positively affects both job performance and work–family balance [44]. In this regard, an increase in leaders’ authentic leadership behaviors contributes to higher levels of employees’ task performance [19,20,21,22,23,45]. However, some studies have reached results that differ from the prevalent findings in the literature and have not found a significant relationship between authentic leadership and task performance.

The importance of task performance is particularly more pronounced in public institutions. In the public sector, low performance is mostly due to the ambiguity of goals, resource constraints and deficiencies in measurement mechanisms. Therefore, effective performance measurement and evaluation systems are critical tools for both increasing internal motivation within the institution and improving the quality of services offered to citizens [46]. Performance measurement provides numerous benefits such as determining priorities, allocating resources efficiently, ensuring accountability, building trust and enhancing service quality.

In this context, task performance reflects the contribution of individual efforts to organizational goals and is regarded as one of the fundamental components of organizational success. Especially in public organizations, increasing task performance is a strategic necessity for achieving sustainable service quality and ensuring organizational effectiveness. Based on these considerations, the research hypothesis formulated in this study is as follows:

H1: 

Authentic leadership positively affects task performance.

2.3. Supportive Organizational Culture

The concept of culture was first defined by Tylor (1871) as a complex whole encompassing the knowledge, beliefs, art, morals and various habits acquired by individuals as members of a society [47]. Organizational culture, in turn, began to become institutionalized in the literature with Weber’s (1904) study examining the relationship between values and capitalism [48], and Pettigrew’s (1979) article titled “On Studying Organizational Culture”, which highlighted the necessity of analyzing organizational culture [49].

Organizational culture has long attracted the attention of researchers as one of the most important elements shaping individuals’ behaviors, attitudes and organizational outcomes [50,51,52]. Although different cultural typologies have been developed in the literature, supportive organizational culture has become one of the prominent concepts in recent years due to its structure that values cooperation, trust and employee well-being.

The concept of supportive organizational culture was introduced into the literature by Wallach (1983) as part of a threefold cultural classification (innovative, bureaucratic and supportive) [53]. In this type of culture, openness in communication, mutual trust, strong relationships among employees and a sense of belonging are emphasized. Schein (1983) [50]. defined organizational culture as the set of fundamental assumptions that a group has developed and shared while solving problems of external adaptation and internal integration and noted that supportive culture arises in work environments where leaders prioritize human values and where mutual respect and trust prevail [54].

Supportive organizational culture has a structure that emphasizes teamwork, promotes open communication, and nurtures mutual trust and a sense of belonging [53,55]. In this culture, leaders adopt a participative, empowering and inclusive leadership style and thereby enhance organizational relationships. There is a communication environment in which employees can express their ideas safely and transparency is encouraged [9]. Friendly relationships, empathy and mutual support are foregrounded, and maintaining strong human relations increases harmony and solidarity among employees [56]. In addition, individuals see themselves as an integrative part of the organization and become strongly committed to shared goals [52], and organizations with this type of culture can adapt more quickly to environmental changes and generate innovative solutions [54].

For a supportive organizational culture to be enduring and sustainable, organizational values must be built on the foundations of trust, cooperation and ethics. Such a culture creates a motivating climate in which mutual trust, open communication and shared purposes prevail, thereby enhancing employee performance and contributing to long-term organizational sustainability. Authentic leadership contributes to the formation of a supportive culture within the organization through its dimensions grounded in relational transparency and ethical values. In this context, the trust- and ethical integrity–based approach of authentic leadership can be regarded as a fundamental mechanism that transforms organizational culture, increases employees’ task performance, and thus strengthens organizational sustainability [57].

Studies have shown that supportive organizational culture is particularly closely related to authentic leadership. Authentic leaders are those who act in harmony with their values and build relationships that are transparent, fair and based on trust [8,58]. This leadership style fosters psychological safety in organizations, facilitates employees’ self-expression, and creates a collaboration-oriented work atmosphere.

The effect of supportive culture on employee performance is quite pronounced. Research has revealed that this cultural type enhances both task performance and contextual performance [59,60]. Increases in employee satisfaction, decreases in turnover intentions, and the promotion of organizational citizenship behaviors demonstrate that supportive culture strengthens organizational effectiveness [61,62]. Chandler et al. (2000) emphasized that supportive culture facilitates innovation and adaptation [63]. Supportive organizational culture ensures that employees perceive organizational support at a high level. Eisenberger et al. (2001) showed that organizational support plays a mediating role between leadership styles and employee outcomes [64]. Özer et al. (2013) highlighted the effects of psychological capital and perceived organizational support on employees’ job satisfaction and performance [65]. Studies also indicate that supportive culture contributes to the reduction in organizational stress and to the increase in employees’ commitment to the organization [55,66].

Literature reviews indicate a lack of empirical studies that directly address the role of supportive organizational culture in the relationship between authentic leadership and task performance. This indicates a need to study how supportive organizational culture affects the relationship between authentic leadership and task performance. In line with the theoretical and empirical findings in the literature, it is proposed that supportive organizational culture may function as a mediating mechanism in the effect of authentic leadership on task performance. It is considered that supportive organizational culture strengthens cooperation within the organization, increases employees’ motivation and, in this way, contributes to the enhancement of task performance.

Supportive organizational culture can be considered an important mediating variable that helps explain the relationship between leadership and performance. Meta-analytic studies in the broader organizational support and climate literature show that supportive work environments are systematically associated with key work outcomes. such as task performance [67]. This supports the expectation that supportive organizational culture may function as a meaningful mechanism linking authentic leadership to employees’ task performance.

In addition, the public sector represents a distinctive context for evaluating leadership–performance relationships. Public organizations operate under more formalized rules, face heightened accountability, and are fundamentally oriented toward public value creation. Accordingly, systematic reviews focusing on the public sector emphasize that contextual constraints and sector-specific outcomes should be considered when theorizing leadership effects [68]. Moreover, reviews of sustainability-related reporting and accountability in public organizations indicate that sustainability is typically assessed through multiple indicators and multi-stakeholder outcomes. Therefore, sustainability-related inferences should be restricted to particular indicators such as measured in the present study (e.g., task performance) [69]. Since sustainability contains multi-dimensional nature, reaching generalizations should be avoided.

Within the framework of the findings discussed in the literature, the following hypotheses are suggested as follows:

H2a: 

Authentic leadership positively affects supportive organizational culture.

H2b: 

Supportive organizational culture positively affects task performance.

H2: 

Supportive organizational culture has a mediating effect in the relationship between authentic leadership and task performance.

2.4. The Relationship Between Authentic Leadership, Supportive Organizational Culture and Task Performance from Sustainability Perspective

The concept of sustainability was first defined on a global scale in the Brundtland Report published in 1987 as “meeting the needs of the present without compromising the ability of future generations to meet their own needs” [70]. This definition revealed that sustainability is not merely an environmental phenomenon but rather expresses a holistic understanding of development that encompasses economic, social and institutional dimensions.

Traditionally evaluated on the axis of profit and efficiency, sustainability goals have today been transformed into a new management paradigm associated with ethical values, stakeholder satisfaction, environmental responsibility and long-term social welfare [31,71]. The “Business Sustainability 3.0” approach developed by Dyllick and Muff (2015) argues that businesses should not only generate economic benefits but also contribute to the societal common good [31]. With this holistic perspective, organizations are expected to develop policies that take into account social justice and ecological balance alongside economic performance in their strategic decision-making processes. Although the idea of sustainability has been conceptualized in the modern era, it can be said that its historical roots lie in the Confucian tradition of Ancient China—in the principle of “moderation” (zhongyong), which emphasizes balance, harmony and interdependence instead of extremes—and in Islamic civilization’s awareness of moderation, respect and sacredness regarding the conservation of nature and the avoidance of waste of resources [72,73]. Redclift (2005), on the other hand, traces the historical origins of sustainability debates back to the post–Industrial Revolution period, emphasizing that the ideology of unlimited production and consumption has disrupted environmental balance and deepened social inequalities [74].

In this context, the idea of environmental sustainability was first systematically articulated in the report The Limits to Growth published in 1972 [75]; subsequently, the Brundtland Report published in 1987 provided the most widely accepted definition of the concept by defining sustainable development as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs” [70]. With the 1992 Rio Summit, the concept of sustainable development gained formal recognition for the first time at the level of international law; and the 1997 Kyoto Protocol marked the first international agreement in history to impose binding greenhouse gas emission reduction targets on developed countries. The 2015 Paris Agreement expanded the limited scope of Kyoto by establishing a global climate settlement that covers both developed and developing countries, thereby making environmental sustainability one of the core elements of the global policy agenda.

The Sustainable Development Goals (SDGs), adopted by the United Nations in 2015 with 2030 as the target year, have demonstrated that sustainability is not limited to the environment alone; it is also closely related to areas such as inclusive and sustainable economic growth for all, shared prosperity, the creation of decent work conditions and economic growth, as well as equality, education, peace, justice, tolerance, openness, social inclusion and innovation [76]. This study, which examines the role of supportive organizational culture in the effect of authentic leadership on task performance from a sustainability perspective, aligns with the United Nations Sustainable Development Goal of “decent work and economic growth”.

2.4.1. The Importance of Sustainability in Leadership

Leaders, with an awareness that they are entrusted for the continuity of future generations, are responsible for establishing and developing the institutional conditions that will make change possible [70]. By shifting employees’ focus from inward-looking to outward-looking, building trust, and redefining success in a way that creates value for society and the planet [31], such leaders lay the ground for enhanced sustainable task performance within organizations.

Sustainability, beyond technical practice, requires a leadership approach grounded in ethical values and a long-term vision. In this context, authentic leaders guide their followers in line with ethical principles and create a climate in which trust and respect become organizational norms and high ethical standards [16]. This supportive climate based on trust enables the institutionalization of a sustainable understanding of leadership and performance by encouraging employee participation that transcends differences in origin, identity and viewpoint.

Authentic leadership, with its dimensions of self-awareness, relational transparency, balanced processing and an internalized moral perspective, is a form of leadership that supports sustainability [5,8]. Authentic leaders strengthen employee participation, establish trust-based relationships and help create alignment between individuals’ core values and organizational goals. In doing so, they reinforce the foundations of sustainable performance at both individual and organizational levels.

By building trust-based, transparent, and ethical relationships with employees and reducing the fear of punishment, authentic leaders create a psychologically safe climate in which ideas can be expressed freely, mistakes are regarded as learning opportunities, and mutual respect is fostered [77]. This climate of mutual trust, as one of the core elements of a supportive organizational culture, strengthens employees’ capacity for emotion regulation, concentration on work effective and coping with stress (mindfulness). As a result, increases are observed in performance-related outcomes such as job satisfaction, organizational commitment, taking responsibility and innovativeness [77]. Therefore, authentic leaders enhance task performance and contribution to the organization not through authoritarian control, but by building a safe and sustainable work environment [77].

2.4.2. The Role of Supportive Organizational Culture in Sustainability

Supportive organizational culture is the fundamental institutional infrastructure that enables sustainability to become embedded at the organizational level. This culture creates a psychologically safe climate in which employees feel valued and where learning, innovation and collaboration are encouraged. The trust, openness and participation-based approach of authentic leaders make it possible for employees to share their ideas without fear of punishment [77]. This safe climate is the practical manifestation of supportive organizational culture.

Cultural environments grounded in fair; participatory and open communication transform the climate of trust into an institutional norm and facilitate the consistent and effective implementation of sustainable management practices [56]. While authentic leadership builds the moral and psychological foundations of sustainability at the individual level, supportive organizational culture ensures the permanence of this influence at the collective level [31]. In the short term, the psychological safety and cooperation generated by authentic leadership evolve, in the long term, the normative aspect of a supportive culture arises, thereby sustainable task performance is nurtured [16].

Therefore, leaders’ trust-based interactions foster a supportive culture within the organization, sustainably strengthening employees’ motivation, sense of belongingness and task performance [57].

2.4.3. The Relationship Between Performance and Sustainability

Sustainable performance goes beyond traditional efficiency indicators and refers to a multidimensional understanding of success that can also encompass social, environmental, and ethical dimensions [70,78]. In the present study, however, sustainability is not measured directly. In addition, task performance is not treated as a sustainability indicator in itself, but as a proximal organizational outcome that may be relevant to sustainable institutional functioning when interpreted together with ethical leadership and supportive cultural conditions.

Research shows that honest and transparent behaviors of leaders lead employees to view them as role models. This, in turn, increases employees’ intrinsic motivation and strengthens their sustainable job performance [79]. Authentic leaders who embrace ethical values build a trust-based culture in organizations, thereby enhancing employees’ levels of psychological safety and sense of belonging. Indeed, Bano, Li and Imran (2024) demonstrate that ethical leadership increases employee performance by fostering trust, respect and diversity in an inclusive organizational climate [16]. These findings indicate that leadership supports sustainable performance by creating a cultural infrastructure grounded in ethical values. From a sustainability perspective, performance should be conceived not merely as individual success but also as the capacity to ensure long-term organizational continuity and to generate societal value.

3. Research Methods

3.1. Study Design and Context

The main purpose of this study, conducted in a metropolitan municipality as a public institution, is to examine the effect of authentic leadership on task performance, to reveal the mediating role of supportive organizational culture in this relationship, and to evaluate the research findings from a sustainability perspective. In this context, determining the direction of the relationship between authentic leadership and task performance and identifying the mediating effect of supportive organizational culture in this relationship constitute one of the primary aims of the study.

A review of the literature shows that the majority of studies investigate the relationships between authentic leadership and various dependent variables, whereas studies focusing on mediating or moderating variables that can explain the underlying reasons for these relationships remain limited. While research on the effect of authentic leadership on task performance mostly reveals that this relationship is positive [19,20,21,22,23,45], some findings indicate that this relationship may not always be significant [27]. These divergent results show that the nature of the relationship between authentic leadership and task performance needs to be investigated more comprehensively. In particular, incorporating mediating variables such as supportive organizational culture into the process in public institutions offers a critical approach to understanding the strength and major mechanisms of this relationship. Considering the growing interest in the social sciences in examining relationships among multiple variables in recent years, it is evaluated that this study, by addressing authentic leadership, task performance and supportive organizational culture together and assessing them within the scope of sustainability, may fill an important gap in the literature and provide original contributions to the field of study.

Authentic leadership, with qualities such as commitment to ethical values, self-awareness, transparency, and balanced information processing, may contribute not only to short-term performance outcomes, but also, indirectly, to longer-term institutional continuity and resilience. In this regard, for leadership effects to generate lasting organizational results, the prevailing culture within the organization must also be supportive in nature. The relationship between authentic leadership and supportive organizational culture therefore points to a managerial approach in public institutions that may strengthen not only short-term performance outcomes, but also broader conditions associated with institutional resilience, trust, and service continuity.

Derived from Şafak Ece’s PhD dissertation [80], this study addresses authentic leadership and supportive organizational culture together and aims to present a conceptual and empirical framework regarding how high performance can be built in public institutions and to contribute to the development of leading strategies for sustainable service delivery in these institutions. The research model developed to test the research hypotheses derived from the literature review is presented in Figure 1.

3.2. Participants and Sampling

This study employed a quantitative, correlational, cross-sectional survey design. The data relied on single-source, self-report questionnaire responses. The online questionnaire was developed in Google Forms (Google LLC, Mountain View, CA, USA) and disseminated via internal organizational communication channels through the municipality’s Quality and Management Systems Branch Directorate to department-level units and their subordinate directorates. Data was collected in a single wave between June 2023 and May 2024.

The study population comprised civil servants and contracted employees working in a metropolitan municipality in Türkiye (approximately 22,000 employees at the time of data collection). The sample was obtained via non-probability convenience sampling. To maximize participation, dissemination targeted personnel across 7 deputy secretariats, 27 departmental directorates, and 107 branch directorates through internal channels. By the end of the data collection period, 1000 employees were invited to participate; 480 responded, and 28 questionnaires were excluded due to incomplete responses. Consequently, 452 fully completed questionnaires were retained for the analyses (approximate response rate ≈ 48%).

Following Gürbüz and Şahin [81], a minimum sample size of 384 respondents (95% confidence level; 5% margin of error) was deemed sufficient for statistical precision. The final sample (N = 452) exceeded this threshold; however, given the use of non-probability sampling and the single-organization setting, the sample size supports statistical precision but does not ensure representativeness. Only fully completed questionnaires were retained for the final dataset (N = 452). Ethical approval was obtained from the Social and Human Sciences Research Ethics Committee of Yıldız Technical University (meeting no. 2021/08), granted on 20 October 2021.

3.3. Data Collection Procedure

The data were collected through an online questionnaire created in Google Forms (Google LLC, Mountain View, CA, USA). The Quality and Management Systems Branch Directorate of the metropolitan municipality disseminated the survey link to the municipality’s official internal email addresses used for internal correspondence. The initial invitation email was sent in June 2023, followed by reminder emails in November 2023 and February 2024 to enhance participation. In addition, the research team held a face-to-face meeting with the Head of the Human Resources Department to discuss the survey process and encourage organizational support for participation. Data collection remained open until May 2024. Participation was voluntary, and survey responses were collected anonymously. Respondents were informed that the survey was intended solely for academic research purposes and that there were no right or wrong answers. The dataset was downloaded and stored on a password-protected drive accessible only to the authors, and all analyses were conducted on de-identified data. The questionnaire began with an eligibility screening item to identify whether respondents were civil servants or contracted employees, and the form was configured to terminate automatically if this item was not answered. All substantive items were set as mandatory. To reduce evaluation apprehension and create a degree of psychological separation between the study variables, the questionnaire was organized into four clearly structured sections and presented with clear instructions. In total, the questionnaire included 41 statements: (1) 8 demographic items; (2) authentic leadership (16 items; 5-point Likert); (3) task performance (9 items; 4-point Likert); and (4) supportive organizational culture (8 items; 4-point Likert).

3.4. Measures

The questionnaire included standardized measures of authentic leadership, task performance, and supportive organizational culture. Scale sources, adaptation procedures, and psychometric properties are reported below. All measures were administered in Turkish. Item translation was conducted collaboratively by two authors who are bilingual in Turkish and English and have training in organizational behavior and quantitative research methods. The Turkish version was then back-translated into English to check linguistic equivalence. Discrepancies between the original and back-translated versions were resolved through discussion and consensus to preserve the intended meaning and improve readability. A pilot study (n = 143) was conducted to assess the reliability and validity of the scales. As the results yielded consistent findings, the main study continued to be conducted.

3.4.1. Measure of Authentic Leadership

Authentic leadership was measured using the Authentic Leadership Questionnaire (ALQ) developed by Walumbwa, Avolio, Gardner, Wernsing, and Peterson (2008) [5]. A three-year license for use of the scale was obtained from Mind Garden Inc. (Menlo Park, CA, USA). The original 16 items were adapted into Turkish using the translation/back-translation procedure described above and were subsequently subjected to validity and reliability analyses. Although the original ALQ was theorized as a higher-order multidimensional construct composed of self-awareness, relational transparency, internalized moral perspective, and balanced processing, dimensionality may vary across cultural and organizational contexts. The original validation study supported a higher-order multidimensional model [5]. However, subsequent adaptation research has shown that the dimensional structure of the ALQ may differ across contexts; for example, Grobler and Grobler (2024) reported a one-factor solution in the South African context [82]. In this respect, the dimensionality of authentic leadership should be evaluated in relation to the cultural and organizational setting in which the scale is applied. In line with the recommendations of Worthington and Whittaker (2006) [83], an Exploratory Factor Analysis (EFA) was first conducted. Item 5 showed substantial cross-loadings on more than one factor and was therefore removed from the scale. After the removal of this item, the remaining 15 items loaded on a single dominant factor, indicating that respondents in this sample perceived authentic leadership as a global rather than clearly differentiated construct. This empirically derived 15-item one-factor structure was then tested using Confirmatory Factor Analysis (CFA). The CFA results indicated acceptable model fit (χ²/df = 3.975, RMSEA = 0.081, GFI = 0.902, AGFI = 0.868, CFI = 0.958, NFI = 0.944, RMR = 0.048, SRMR = 0.032), supporting the construct validity of the one-factor solution. Factor loadings ranged from 0.57 to 0.91, and the internal consistency coefficient was high (Cronbach’s alpha = 0.96). The one-factor solution explained approximately 66% of the total variance.

Therefore, authentic leadership was operationalized as a unidimensional construct in the present analyses. The scale was rated on a 5-point Likert scale coded from 0 to 4, ranging from “never” (0) to “always” (4).

3.4.2. Measure of Task Performance

Task performance was measured using 9 items from the task performance dimension of the scale developed by Goodman and Svyantek (1999) [84]. The original instrument comprises 25 items across three dimensions; in line with Goodman and Svyantek’s (1999) operationalization, this study used the 9-item task performance subscale. The selected items were adapted into Turkish using the translation/back-translation procedure described above, followed by validity and reliability analyses. No reverse-coded items were included. Exploratory Factor Analysis (EFA) indicated a unidimensional structure, which was subsequently tested through Confirmatory Factor Analysis (CFA).

Task performance was assessed via employees’ self-ratings on a 4-point Likert scale (1 = strongly disagree, 4 = strongly agree). Because the items are formulated in a general manner and do not refer to a specific time frame, the measure captures overall perceived task performance (i.e., typical performance in the current job role) rather than performance within a defined period.

Model-fit criteria were evaluated using widely cited guidelines in the SEM literature [85,86]. When the fit indices related to the CFA were examined, it was determined that the ratio of the chi-square value to the degrees of freedom (χ²/sd = 3.556) indicated an excellent level of fit. This finding shows that the single-factor structure of the 9-item scale was confirmed and that the construct validity of the scale was achieved. The Cronbach’s alpha internal consistency of the scale was calculated as 0.91, and it was found that it explained approximately 60% of the total variance. The scale is rated on a 4-point Likert scale, ranging from “strongly disagree (1)” to “strongly agree (4)”.

3.4.3. Measure of Supportive Organizational Culture

Supportive organizational culture was measured using 8 items (items 2, 5, 8, 9, 15, 16, 17 and 22) from the relevant dimension of Wallach’s (1983) organizational culture scale [53]. The scale was translated from English into Turkish, and then back-translation was used to check linguistic equivalence. As a result of the Exploratory Factor Analysis (EFA), it was observed that the scale had a single-factor structure and explained approximately 70% of the total variance. This structure was then tested through Confirmatory Factor Analysis (CFA).

When the fit indices related to the CFA were examined, it was determined that the chi-square/df ratio of 3.498 indicated an excellent level of fit, while the RMSEA value of 0.074 indicated an acceptable level of fit. These findings show that the single-factor structure of the 8-item scale was confirmed and that construct validity was achieved. The Cronbach’s alpha internal consistency coefficient of the scale was calculated as 0.94. The items of the scale are rated on a 4-point Likert type, ranging from “does not describe my organization (1)” to “mostly describes my organization (4)”.

3.5. Data Analysis

The survey data was analyzed using IBM SPSS 26.0 and IBM SPSS AMOS 22.0(IBM Corp., Armonk, NY, USA) software. The assumption of normality was tested through the Kolmogorov–Smirnov test and by examining skewness and kurtosis values, and it was concluded that the data were normally distributed. Composite scores were computed as the mean of item responses (no standardization), with higher scores indicating higher levels of the construct. We preserved the original item structure and response format to maintain comparability with prior validation studies, and computed mean composite scores to keep the metric consistent across constructs with different item counts.

Data screening was conducted prior to hypothesis testing. No missing data were observed in the final dataset because the questionnaire was administered via Google Forms with all items set as mandatory. Additionally, respondents who did not indicate their employment status (civil servant vs. contracted employee) at the screening step could not proceed, and incomplete/ineligible entries were not retained as completed cases. Therefore, the analytic dataset contained complete responses for all variables (N = 452). Demographic variables were collected and are reported descriptively; however, they did not indicate any significant differences. Overall, demographic variables were not intended to be the focus of the study in the presented main research model.

In addition, we assessed potential careless responding by examining response-pattern indicators (e.g., straight lining/low within-person variance and unusually repetitive patterns). Because the survey export did not provide reliable response-time metadata, response-time screening could not be conducted. No pervasive evidence of patterned random responding was observed based on these pattern checks. However, this study did not include attention-check items; therefore, response-pattern diagnostics are informative but do not provide definitive evidence. Nevertheless, future studies should include attention-check items and/or objective response-time flags to further strengthen data-quality assurance.

To assess common method bias, Harman’s single-factor test was conducted; the first factor accounted for 40.78% of the variance. Although this is below the conventional 50% heuristic, Harman’s test alone cannot rule out common method bias. Because authentic leadership, supportive organizational culture, and task performance were all measured through self-reports from the same respondents at the same time period, the observed associations may be partly inflated by shared method variance. More specifically, the mediation pattern may partly reflect perceptual congruence: respondents who evaluate their leaders positively may also be more likely to evaluate the organizational climate and their own task performance positively. Accordingly, the findings should not be interpreted as purely behavioral relationships, and the mediation results should be read with caution. Procedural remedies were applied by ensuring anonymity, using neutral item wording, and separating constructs into distinct questionnaire sections. Future research, therefore, should evaluate method variance more rigorously through multi-source designs and, where possible, common latent factor or ULMC approaches within CFA.

Parametric tests were preferred for data analysis. Relationships between two variables were examined using Pearson correlation; descriptive statistics were reported in terms of frequency, mean and standard deviation values; for the demographic variables differences between two groups were analyzed with independent samples t-test, and differences among more than two groups were examined using one-way ANOVA. In addition, the direction and strength of the relationships among the variables as well as the mediation effects were tested using the SPSS PROCESS Macro Version 4.2 (Andrew F. Hayes, Columbus, OH, USA). Outliers and influential observations were screened using standardized residuals (|ZRE| > 3) and Cook’s distance (Cook’s D > 4/N) and sensitivity analyses were conducted by re-estimating the mediation model after excluding these cases.

4. Results

4.1. Demographic Results

The demographic characteristics of the personnel in public sector who participated in the study are summarized in

Table 1. Demographic characteristics of the participants.

Demographic Variables	Groups	n	%
Age	18–29 years	58	12.8%
	30–39 years	128	28.3%
	40–49 years	162	35.8%
	50 years and above	104	23.0%
Gender	Female	129	28.5%
	Male	323	71.5%
Years of Professional Experience	Less than 5 years	59	13.1%
	6–10 years	43	9.5%
	11–15 years	89	19.7%
	16–20 years	119	26.3%
	21 years and above	142	31.4%
Years at Current Institution	Less than 5 years	135	29.9%
	6–10 years	46	10.2%
	11–15 years	90	19.9%
	16–20 years	95	21.0%
	21 years and above	86	19.0%
Organizational Position	Staff	346	76.5%
	Manager	106	23.5%
Employment Status	Civil Servant	359	79.4%
	Contracted Employee	93	20.6%
Educational Background	Primary & High School	43	9.5%
	Associate Degree	60	13.3%
	Bachelor’s Degree	215	47.6%
	Postgraduate Degree	134	29.6%

. Of the participants, 35.8% are between 40 and 49 years of age. In terms of gender distribution, males predominate with a rate of 71.5%. The proportion of those with 21 years or more of professional seniority is 31.4%. The rate of participants who have been working in the current organization for 1–5 years is 23.9%.

Among the participants, 76.5% are employees (non-managerial staff), 79.4% hold civ-il servant status, and 47.6% are bachelor’s degree graduates. Based on departmental di-rectorates, the highest participation came from units affiliated with the Fire Department, with 84 respondents. This group is followed by the Directorate of Municipal Police (10.6%), the Transportation Department (9.7%) and the Human Resources and Training Department (9.1%).

4.2. Results on Factor and Reliability Analyses of the Measurement Instruments

In this section, the results of analysis related to the variables in the study are presented. First, factor structure and reliability analyses were conducted for authentic leadership, task performance and supportive organizational culture scales, and subsequently, correlation and regression analyses were applied to test the hypotheses. The results of the factor and reliability analyses for the scales are reported in

Table 2. Factor and reliability analysis results of the scales.

Factor Name	Item	Factor Loading	Item-Total Correlation	Eigenvalue	Explained Variance (%)	Cronbach’s α
Authentic Leadership	Item 1	0.781	0.747	9.953	66.353	0.963
	Item 2	0.768	0.732
	Item 3	0.890	0.866
	Item 4	0.726	0.688
	Item 6	0.782	0.751
	Item 7	0.660	0.626
	Item 8	0.625	0.588
	Item 9	0.880	0.855
	Item 10	0.801	0.768
	Item 11	0.888	0.863
	Item 12	0.899	0.875
	Item 13	0.893	0.868
	Item 14	0.854	0.825
	Item 15	0.873	0.845
	Item 16	0.834	0.805
KMO = 0.968; Bartlett’s Test (df = 105) = 6267.286; p < 0.001
Task Performance	Item 1	0.667	0.583	5.407	60.083	0.914
	Item 2	0.766	0.693
	Item 3	0.807	0.741
	Item 4	0.827	0.764
	Item 5	0.747	0.677
	Item 6	0.700	0.624
	Item 7	0.792	0.726
	Item 8	0.840	0.782
	Item 9	0.812	0.747
KMO = 0.918; Bartlett’s Test (df = 36) = 2420.577; p < 0.001
Supportive Organizational Culture	Item 1	0.848	0.796	5.640	70.501	0.940
	Item 2	0.756	0.688
	Item 3	0.862	0.813
	Item 4	0.842	0.789
	Item 5	0.843	0.790
	Item 6	0.875	0.830
	Item 7	0.823	0.765
	Item 8	0.863	0.814
KMO = 0.926; Bartlett’s Test (df = 28) = 2918.914; p < 0.001

.

The construct validity of the authentic leadership, task performance and supportive organizational culture scales used in the study was tested through both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). To assess the adequacy of the data for factor analysis, the Kaiser–Meyer–Olkin (KMO) measure and Bartlett’s Test of Sphericity were employed. The significant results of Bartlett test (p < 0.001) indicate that there are statistically significant relationships among the variables in the scales [87]. In addition, KMO values above 0.60 for all scales and the significance of the Bartlett test demonstrates that the data are adequate for conducting factor analysis [87].

Regarding authentic leadership, the Turkish adaptation of the 16-item Authentic Leadership Questionnaire developed by Walumbwa et al. (2008) was examined through EFA and CFA [5]. The EFA conducted during the scale adaptation process indicated that the Turkish version did not reproduce the original multidimensional structure in the present sample. Item 5 showed substantial cross-loadings on more than one factor and was therefore removed from the scale. Following the removal of this item, the remaining 15 items loaded on a single dominant factor, yielding a unidimensional structure. The one-factor solution explained 66% of the total variance, and the internal consistency of the scale was high (Cronbach’s alpha = 0.96). This empirically derived 15-item one-factor structure was then tested using CFA. The results indicated acceptable model fit (χ²/df = 3.975, RMSEA = 0.081, GFI = 0.902, AGFI = 0.868, CFI = 0.958, NFI = 0.944, RMR = 0.048, SRMR = 0.032), supporting the construct validity of the one-factor solution. Standardized factor loadings ranged from 0.57 to 0.91. Taken together, these findings supported the use of authentic leadership as a unidimensional construct in the subsequent analyses.

To measure task performance, the 9-item scale developed by Goodman and Svyantek (1999) was used [84]. The analysis confirmed its unidimensional structure; the scale explained 60% of the total variance, and its Cronbach’s alpha value was found to be 0.91. To measure supportive organizational culture, 8 items belonging to the supportive dimension of Wallach’s (1983) organizational culture scale were evaluated [53]. The analyses showed that the scale displayed a single-factor structure, explained 70% of the total variance, and had a Cronbach’s alpha coefficient of 0.94. According to exploratory studies in the literature, an internal consistency value above 0.70 is deemed sufficient [88], these values reflect a very strong level of reliability.

4.3. Descriptive Statistics and Correlation Analysis Results

Pearson Correlation Analysis was conducted to determine the means, standard deviations, and interrelationships of the variables used in the study, and the results are presented in

Table 3. Descriptive statistics and correlation analysis results for research variables.

No.	Variables	Mean	SD	1	2	3
1	Authentic Leadership	2.38	1.01	1
2	Supportive Organizational Culture	2.62	0.84	** 0.671	1
3	Task Performance	3.38	0.46	0.069	** 0.146	1

** p < 0.01 (2-tailed).

. The mean values for authentic leadership, task performance and supportive organizational culture were found to be ($\overline{x}$ = 2.38), ($\overline{x}$ = 3.38) and ($\overline{x}$ = 2.62), respectively. These results indicate that participants’ perceptions of authentic leadership and supportive organizational culture are at a moderate level, whereas their perceptions regarding task performance are relatively higher (Table 3).

The findings of the correlation analysis indicate that there is a strong and positive relationship between authentic leadership and supportive organizational culture (r = 0.671; p < 0.01). This result shows that leaders’ authentic attitudes and behaviors make a significant contribution to the formation of employees’ perceptions of a supportive culture. In contrast, no significant relationship was found between authentic leadership and task performance (r = 0.069; p > 0.05). This finding suggests that the effect of authentic leadership on task performance may not be direct but may instead be affected through indirect variables such as cultural factors.

On the other hand, although the relationship between supportive organizational culture and task performance is weak, it is positive and significant (r = 0.146; p < 0.01). This indicates that the presence of a supportive culture in organizations may play a partial yet meaningful role in enhancing employees’ task performance. This relationship reveals that employees tend to perform their duties more effectively in a supportive organizational climate. The findings are consistent with studies in the literature that emphasize the indirect effects of the interaction between authentic leadership and supportive culture on employee outcomes [5,29].

Overall, these results show that authentic leadership and supportive organizational culture are mutually reinforcing structures in public institutions, and this interaction carries significant potential for improving employee performance. However, the absence of a direct effect of authentic leadership on task performance supports the assumptions that cultural factors may play a mediating role in this relationship.

4.4. Hypothesis Testing

In order to test the hypotheses and examine the mediating variables in the study, the Process Macro program developed by Andrew F. Hayes (2018) was used, and the analyses were conducted with the bootstrap method based on 5000 resamples [89]. The regression analyses were carried out within the framework of Model 4, and the relationships in the research model presented in Figure 1 were tested. In this context, the effect of authentic leadership on task performance was evaluated by taking into account the mediating role of supportive organizational culture.

Specifically, we estimated path a (authentic leadership → supportive organizational culture), path b (supportive organizational culture → task performance controlling for authentic leadership), and the direct effect c′ (authentic leadership → task performance controlling for supportive organizational culture). The indirect effect (a × b) was assessed using 95% bootstrap confidence intervals (5000 resamples); mediation was supported when the 95% bootstrap CI did not include zero.

As robustness checks, we conducted covariate-adjusted mediation analyses (PROCESS Model 4; 5000 bootstrap resamples) and outlier/influence sensitivity analyses. Covariates included age, gender, tenure in profession, tenure in the organization, organizational position (employee vs. manager), education level (primary/high school, associate, bachelor, graduate), and employment status (civil servant vs. contracted). Outliers were screened using standardized residuals (|ZRE| > 3), and influential observations were screened using Cook’s distance (Cook’s D > 4/N; N = 452; threshold = 0.00885).

When the results in

Table 4. Findings on the mediating role of supportive organizational culture in the effect of authentic leadership on task performance.

	Variable	Regression						Model Summary
		β	SE	t	p	LLCI	ULCI	p	R2	F
Dependent Variable: TP	Constant	3.314	0.056	59.288	0.000	3.204	3.424	0.146	0.005	2.123
	AL	0.031	0.022	1.457	0.146	−0.011	0.074
Dependent Variable: SOC	Constant	1.300	0.075	17.290	0.000	1.152	1.448	0.000	0.450	367.747
	AL	0.557	0.029	19.177	0.000	0.500	0.614
Dependent Variable: TP	Constant	3.184	0.072	44.508	0.000	3.043	3.324	0.006	0.023	5.230
	AL	−0.024	0.029	−0.843	0.400	−0.081	0.032
	SOC	0.100	0.035	2.881	0.004	0.032	0.168

(AL = Authentic Leadership; SOC = Supportive Organizational Culture; TP = Task Performance; SE = Standard Error).

are examined, it is seen that the total effect of authentic leadership on task performance is not statistically significant (β = 0.031; p > 0.05). This finding indicates that increases in perceptions of authentic leadership do not lead to a direct change in task performance. In addition, the fact that the confidence interval (LLCI = −0.011; ULCI = 0.074) includes zero supports the conclusion that the relationship is not significant. Therefore, hypothesis H1, which stated that “authentic leadership positively affects task performance,” was rejected.

In contrast, authentic leadership was found to have a significant effect on supportive organizational culture (β = 0.557; p < 0.001). The explanatory power of the model is high (R² = 0.450), and the fact that the confidence intervals do not include zero (LLCI = 0.500; ULCI = 0.614) supports the significance of this relationship. Accordingly, hypothesis H2a, which stated that “authentic leadership positively affects supportive organizational culture,” was accepted.

When authentic leadership and supportive organizational culture were included in the model together, it was observed that the effect of supportive organizational culture on task performance was statistically significant (β = 0.100; p < 0.01). Although the explanatory strength of the model is not very high (R² = 0.023), this result supports hypothesis H2b, which stated that “supportive organizational culture positively affects task performance”.

The findings presented in

Table 5. Findings on the direct and indirect effects of supportive organizational culture in the relationship between authentic leadership and task performance.

Total Effect	Effect	SE	LLCI	ULCI	t	p
AL → TP	0.031	0.022	−0.011	0.074	1.457	0.146
Direct Effect	Effect	SE	LLCI	ULCI	t	p
AL → TP	−0.024	0.029	−0.081	0.032	−0.843	0.400
Indirect Effect		Effect	BootSE	BootLLCI	BootULCI
AL → SOC → TP		0.056	0.020	0.017	0.096
Standardized Indirect Effect		Effect	BootSE	BootLLCI	BootULCI
AL → SOC → TP		0.122	0.044	0.038	0.212

(AL = Authentic Leadership; SOC = Supportive Organizational Culture; TP = Task Performance; SE = Standard Error; BootSE = Bootstrap Standard Error).

show that the total effect of authentic leadership on task performance is not significant (β = 0.031; p = 0.146). In addition, it was determined that the direct effect also does not reach a statistically significant level (β = −0.024; p > 0.05). However, according to Andrew F. Hayes’ mediation analysis approach, the non-significance of the direct effect does not mean that the independent variable has no effect on the dependent variable at all. Rather, it indicates that the effect of the independent variable may occur indirectly through a mediating variable [89].

Indeed, with the inclusion of supportive organizational culture as a mediating variable in the model, it was found that the indirect effect between authentic leadership and task performance became significant (β = 0.056; BootLLCI = 0.017; BootULCI = 0.096). The fact that the bootstrap confidence intervals do not include zero confirms this mediation effect. Moreover, the significance of the standardized indirect effect (β = 0.122; BootLLCI = 0.038; BootULCI = 0.212) highlights the importance of the indirect relationship. These results indicate that supportive organizational culture plays a full mediating role in the relationship between authentic leadership and task performance. Therefore, the hypothesis stating that “supportive organizational culture has a mediating effect in the relationship between authentic leadership and task performance” (H2) is supported.

Sensitivity analyses further supported the robustness of the mediation inference. Excluding cases with |ZRE| > 3 (n = 2; N = 450), the bootstrapped indirect effect of authentic leadership on task performance via supportive organizational culture remained significant (indirect effect = 0.0571, 95% BootCI [0.0200, 0.0976]). Excluding influential observations using Cook’s D > 4/N (n = 23; N = 429), the indirect effect also remained significant (indirect effect = 0.0928, 95% BootCI [0.0539, 0.1338]). Importantly, in the Cook’s-filtered sample (N = 429), the indirect effect remained significant after adjusting for demographic variables, including employment status (indirect effect = 0.0849, BootSE = 0.0208, 95% BootCI [0.0445, 0.1257]), while the direct effect remained non-significant (p = 0.1129). Overall, these results indicate that supportive organizational culture plays a robust mediating role in the relationship between authentic leadership and task performance, although results should be interpreted with appropriate caution given the cross-sectional, single-source design.

5. Discussion

This study examines the effect of authentic leadership on task performance in a metropolitan municipality and the mediating role of supportive organizational culture in this relationship. In the study, task performance is addressed as the extent to which activities that directly contribute to technical processes or indirectly contribute by ensuring the provision of necessary materials and services.

In public institutions, low performance often stems from structural problems such as misalignment between objectives, the use of measurement tools that lack reliability and validity, and the limitations of resources. Eliminating these structural problems depends not only on governments’ adoption of new public management approaches or development of performance indicators, but also on strengthening the leadership styles and organizational culture dynamics that underlie these indicators. When high productivity is aimed with limited resources, improving measurement–evaluation frameworks alone is not sufficient. The social networks, trust mechanisms, and cultural climate must also be transformed.

Therefore, in order for public organizations to use their existing resources more effectively and efficiently and to achieve sustainable effectiveness, efficiency, and quality objectives, it is of strategic importance for sustainable performance to identify the leadership styles that affect task performance as well as to determine which regulatory/improving steps should be taken in the organizational culture. This study significantly explains how the nature of authentic leadership, which is based on trust, openness, and consistency, strengthens task performance through supportive organizational culture, thereby offering a framework for improving performance in public administration from the aspect of sustainability.

In this study, sustainability is not empirically presented or quantitatively measured, but rather presented in a contextual approach assuming its relationship with such organizational indicators as supportive organizational culture and authentic leadership that triggers performance. Since authentic leadership contains ethical issues both in and out of the organization and leads organizational activities in regard to using resources effectively and caring about employees’ career development opportunities and well-beings as well as sensitivity to environmental issues, it is assumed that this type of leadership is congruent with sustainable organizational processes and activities. A positive supportive organizational culture, on the other hand, helps the achievement of organizational goals through the use of effective leadership skills by motivating employees for a better performance. When the culture contains such sustainability values as green HR activities with the awareness of efficient use of sources, transparency, sensitivity to the vanishing environmental resources, in this regard, will be among strategic considerations of organizations. Public organizations in Turkey including the metropolitan municipalities, are strategically concerned about sustainability issues and follow the steps of achieving sustainable activities particularly in recent years.

The research was conducted with 452 civil servants and contracted personnel working in a metropolitan municipality in Türkiye. The model indicates that authentic leadership did not exert a statistically significant direct effect on task performance, whereas supportive organizational culture fully mediated this relationship in between the variables. In substantive terms, this pattern suggests that in public organizations, leadership may influence task execution less through direct interpersonal interactions but more through the supportive norms, routines, and climate that become institutionalized around leadership practices.

The literature review shows that authentic leadership positively affects task performance in most studies [19,20,21,22,23,24,25]. However, there are also studies that do not find a significant relationship between authentic leadership and task performance [26,27]. In this study as well, no direct relationship was found between authentic leadership and task performance. In this respect, the study is similar to the findings of Alilyyani (2022) and Taşkın (2023) [26,27]. What differentiates this research from these studies is the inclusion of supportive organizational culture as a mediating variable in the relationship between authentic leadership and task performance, and the attempt to explain the effect of this cultural mechanism.

The full mediation pattern is consistent with studies suggesting that authentic leadership does not necessarily exert a uniformly strong direct effect on performance; rather, its influence often operates through intermediate social and relational processes such as psychological safety, trust, and leader–member exchange. In public organizations, a supportive cultural climate may be particularly critical because formalized rules, role clarity, and procedural compliance constrain initiative-based performance variation of leaders more strongly than in many private-sector settings. Accordingly, a supportive culture can function as an enabling infrastructure that transmits ethical and transparent leadership signals into day-to-day coordination, cooperation, and task execution.

According to Social Exchange Theory, when employees do not believe that leader–member interactions based on reciprocity will bring concrete benefits or rewards, their tendency to invest emotionally and behaviorally to their relationship with the leader weakens [90]. When the characteristics of authentic leadership, such as reliability, transparency, and sincerity, do not sufficiently overlap with employees’ perceptions of self-interest, the “perceived instrumentality” of these characteristics in achieving performance improvements remains low. In the public sector, job security, standardized working conditions, and strong external motivational factors may shift employees’ focus from long-term relational processes towards short-term and tangible gains. This may weaken the direct effect of authentic leadership behaviors on task performance. In addition, the limited emphasis on charisma inherent in authentic leadership may make it more difficult for the leader to be perceived as an “inspiring” or “high-impact” figure. The institution’s entrenched bureaucratic culture and its potential towards traditional leadership practices may also constrain the reflection of the positive aspects of authentic leadership in organizational routines and individual performance behaviors. Overall, it appears that the emergence of a relationship between authentic leadership and task performance is determined by the perceived levels of reciprocity, instrumentality, and cultural support in the work environment.

Alternative explanations for the non-significant direct effect of leadership on performance should also be considered. First, self-report bias regarding performance may have reduced the ability to detect more realistic behavioral differences. Second, because the mean level of self-rated task performance was relatively high, a ceiling effect or restricted variance may have weakened the direct association. Third, common method bias may have influenced the mediation pattern by increasing consistency among respondents’ evaluations of leadership, culture, and their own performance. Finally, performance in public organizations is likely shaped by many additional factors—such as workload, formal rules, job security, role clarity, resources, strict rules and procedures and performance management systems—that were not included in the present model.

A supportive organizational culture creates a foundation that enables employees to exhibit higher task performance by increasing their identification with the organization, job satisfaction, and organizational commitment. The findings of this study show that the effect of authentic leadership on task performance emerges through supportive organizational culture, and therefore authentic leadership alone may not be sufficient to produce higher task performance unless it is supported by a culture that reinforces these behaviors.

Correlation analyses reveal that authentic leadership strongly and positively affects supportive culture. Studies in the literature also support the results obtained from this research. Yetkin (2016) shows that authentic leadership strengthens supportive organizational culture by increasing employees’ psychological capital (hope, self-efficacy, optimism, and resilience) [28]. It has been found that authentic leaders increase job satisfaction and task performance and create an indirect effect on affective commitment through job satisfaction by positively affecting work–family-friendly supportive cultures [29]. Nurlianti, Hidayati and Wijaya (2023) reveal that the interaction between authentic leadership and organizational culture increases employees’ job satisfaction and affective commitment [91]. Although the number of studies focusing on the relationship between authentic leadership and supportive culture is limited, Baykal’s (2020) findings show that authentic leadership increases perceived organizational support, which is consistent with the results of this study [92]. When all these results are considered together, it is understood that authentic leaders strengthen psychological safety, team cohesion, and sense of belongingness through open and honest communication as well as practices that promote cooperation. This steadily increases task performance through job satisfaction and commitment. In fact, these findings also demonstrate that authentic leadership influences task performance through variables such as psychological safety, satisfaction, and commitment.

Among this study’s findings, the positive and significant effect of supportive organizational culture on task performance is also consistent with the literature [93,94,95] studies directly examining the mediating role of supportive organizational culture in the relationship between authentic leadership and task performance are not frequently encountered in the literature, the findings obtained in this research indicate that authentic leadership increases task performance through supportive organizational culture, thus making an original contribution to the literature.

The study’s results show that one of the main mechanisms strengthening the relationship between authentic leadership and task performance is supportive organizational culture, which promotes trust, solidarity, and cooperation within the organization. Therefore, organizational context and cultural structures play an important role in the relationship between leadership and employees’ task performance. The open and honest communication of authentic leaders facilitates employees’ free expression of their ideas. Such attitudes of authentic leaders create a trust-based atmosphere within the organization. Supportive organizational culture makes this atmosphere of trust permanent, thereby increasing employees’ job satisfaction, motivation, and commitment and positively affecting task performance.

In public institutions with rigid hierarchical structures, employees’ performance is mostly shaped within the framework of compliance with procedures and sense of duty. Supportive organizational culture, however, can partially soften this rigidity by encouraging employees to take on more responsibility, show initiative, and display prosocial behaviors that go beyond their formal job descriptions.

The study reinterprets prior findings on the relationship between authentic leadership and task performance through a cultural transmission mechanism and suggests that supportive organizational culture is a key mediating variable in this relationship. At the same time, the explanatory power of the final task-performance model is modest (R² = 0.023). Therefore, supportive organizational culture should be interpreted as one of the meaningful predictors among many others, rather than being as a single dominant explanation of employee performance outcomes.

In this study, the sustainability perspective is presented conceptually rather than as a directly measured construct by linking ethical and transparent leadership, supportive cultural norms, and decent work conditions to the long-term continuity and quality of public service delivery. Because sustainability outcomes—such as service quality continuity, stakeholder well-being indicators, resource efficiency, or ESG-related metrics—were not directly measured, task performance should be interpreted as a proximal and self-reported organizational outcome rather than as a comprehensive indicator of sustainability. Accordingly, the study does not claim to empirically demonstrate sustainability; instead, it offers theoretically grounded implications regarding how authentic leadership and supportive organizational culture may support conditions associated with sustainable institutional functioning by considering this study’s findings.

Accordingly, the study’s sustainability contribution lies in clarifying organizational processes and procedures in such a way that: ethical and transparent leadership may contribute to more sustainable institutional functioning when its influence is embedded in supportive cultural norms that reinforce trust, participation, and continuity in public service processes.

The study contributes primarily to explain the findings from the aspect of Social Exchange Theory. From this perspective, the fact that authentic leadership strengthens supportive organizational culture but does not produce a direct effect on public employees’ task performance indicates that exchange processes in the public sector may be shaped less by immediate leader-based reciprocity and more by institutionally embedded cultural conditions. Public employees may not always interpret leader qualities as direct performance incentives; instead, factors such as job security, standardized procedures, and formal accountability structures may become more salient determinants of task performance. Consequently, the finding that supportive organizational culture demonstrates a full mediating role suggests that exchange processes are transmitted through the broader organizational climate as well as interpersonal interaction.

An additional point that should be considered concerns the dimensionality of the authentic leadership measure. Although the original ALQ was conceptualized as a multidimensional construct, the findings in the present study supported a one-factor solution. This suggests that employees in this municipal/public-sector context tended to perceive authentic leadership as an integrated overall leadership pattern rather than as clearly differentiated subdimensions. This interpretation is also consistent with the view that the dimensionality of adapted leadership scales may vary across cultural and organizational contexts.

The research findings show that the competencies of authentic leaders—such as self-awareness, relational transparency, balanced processing of information, and an internalized moral perspective—are not sufficient on their own. These characteristics are reflected in performance more strongly when they are rather integrated with supportive cultural norms such as fair processes, participatory decision-making mechanisms, open communication, and psychological safety. It is considered that, in order to achieve sustainable performance in long term, organizations need regular and evidence-based feedback systems, participatory decision-making protocols, fair and transparent performance–reward assessments, 360° feedback, developing supportive cultural values and practices, empowering job designs, learn by mistakes experiences, and standards that prioritize openness in internal communication. In addition, it is recommended that authentic leadership training, coaching and mentoring programs, and team rituals focused on psychological safety and authenticity should be institutionalized from a sustainability perspective. It is important that corporate performance indicators are addressed together with ethical process criteria, stakeholder well-being indicators, public service quality, and dimensions of trust, and integrated strategic goals. Future work should also integrate broader indicators such as service quality, stakeholder well-being, and other sustainability-related outcomes rather than relying solely on self-reported task performance.

However, this study has several limitations. First, the research was conducted with public-sector employees in a single metropolitan municipality in Türkiye; therefore, the findings reflect a single-organization, public-sector setting within a specific cultural and geographical context and should not be generalized broadly across all public institutions, private-sector contexts, or other occupational groups. Different organizational, sectoral, and cultural contexts may yield different results. Second, the sample was obtained through non-probability convenience sampling, which limits representativeness even though the final sample size was statistically adequate. Third, because the study relied on a cross-sectional design, causal inference and temporal ordering remain limited, and the findings do not capture longer-term changes. Fourth, to have an access to actual task performance measurement outcomes, particularly in public organizations in Turkey is such a difficult task in terms of their confidentiality and bureaucratic procedures. Therefore, self-reported task performance of employees were used as data. Accordingly, the sample might have reflected comparatively higher rates of task performance which is one of the limitations of this study. The relatively high mean score raises the possibility of ceiling effects or restricted variance. There can be a social desirability or self-enhancement bias with self-assessment of performance, especially within an organizational context. Although procedural remedies were applied, the mediation findings should still be interpreted cautiously because part of the observed pattern may reflect shared perceptions rather than fully behavioral relationships. Another limitation concerns the measurement structure of authentic leadership. Although the original ALQ was developed as a multidimensional construct, the Turkish-adapted version used in this study yielded a one-factor solution in this sample. Therefore, the findings should be interpreted as reflecting employees’ overall perception of authentic leadership rather than its distinct subdimensions. Future studies may compare one-factor, four-factor, and higher-order models across different public-sector and cultural contexts to further examine the dimensionality of the construct. Future research should therefore employ multi-source performance assessments (e.g., supervisor ratings, peer ratings, or objective indicators), broader or probability-based sampling strategies, longitudinal or multi-wave designs, direct multi-indicator sustainability outcomes, and latent SEM mediation models that estimate indirect effects while explicitly accounting for measurement error.

6. Conclusions

Considering the findings of the study and discussions conducted in the previous sections, the general conclusion points can be drawn as follows:

• Authentic leadership did not show a significant direct effect on task performance in the studied public-organization context.
• Authentic leadership positively predicted supportive organizational culture, which in turn positively predicted task performance.
• Supportive organizational culture fully mediated the relationship between authentic leadership and task performance (bootstrapped indirect effect).
• Sensitivity and covariate-adjusted analyses supported the robustness of the mediation inference.
• Given the cross-sectional, single-source design, non-probability convenience sampling, and single-municipality setting, causal inferences and broad generalizations should be made cautiously.
• Although supportive culture was a significant predictor, the explained variance in task performance was modest, consistent with the multifactorial nature of performance in public organizations.
• From a sustainability perspective, leadership effects appear more likely to transfer into proximal performance outcomes when embedded in supportive cultural norms; future studies, therefore, should test direct sustainability outcomes using multi-source and multi-indicator designs.