Sustainability and Politics: Explaining the Emergence of the 2020 Budapest Climate Assembly

The relationship between political participation and the pursuit of sustainability at the local level has been investigated extensively in the literature. In this content, the emergence and extensive use of citizens’ assemblies receive particular attention. Much research focuses on the functioning of these assemblies and potential impact in the community. However, we know very little about why such initiatives occur. This article fills that gap in the literature and aims to explain why a citizens’ assembly on climate change was organized. It focuses on the Citizens’ Assembly in Budapest (Hungary), organized in the fall of 2020 with randomly selected citizens. The findings illustrate that although civil society initiated the deliberative process, the prime mover of the Citizens’ Assembly was political. Local politicians pursued this objective to fulfil their election pledges, ensure ideological consistency and promote sustainability.


Introduction
Citizens' assemblies have gained momentum in the last two decades as they provide useful forums for high-quality deliberation and citizen decision-making [1]. There is great variety in the topics addressed by these deliberative mini publics throughout the world. Recently, citizens' assemblies have also been used in the field of climate change, mainly with the aim to identify existing problems and suggest specific policies. Earlier research shows how assemblies advance climate action, educate the citizenry, how proposals are generated (including the functioning of these meetings), and their consequences on decision-making [2][3][4][5]. In spite of this burgeoning literature, we know very little about why climate assemblies are organized. Understanding the emergence of citizens' assemblies is important for at least two reasons. On the one hand, it can shed light on the institutional and societal factors that favor the involvement of citizens in deliberation. Such knowledge will allow policy makers to act in broadening deliberation to additional policy areas. On the other hand, the analysis reflects the dynamic of deliberation on an issue that is increasingly salient.
This article aims to address this gap in the literature and seeks to explain why the citizens' assembly on climate change was organized in Budapest in 2020. Our quest for an answer is based on five potential drivers derived from the literature on deliberative mini-publics: the political interest of the promoters, their ideology, the desire to create a local identity, the pursuit of a broader economic interest for the community, and the desire to ensure sustainability. Budapest is an excellent case for analysis due to the differences in ideological orientation between local government and the central government, which are explained in detail in the following paragraph and in the research design section. Our qualitative analysis rests on a combination of document analysis (election manifestos, policy documents and information documents) and six semi-structured interviews with politicians and experts involved in the process conducted between June and October 2020.
The city of Budapest is run by a political party that opposes the Hungarian Government. The city mayor Gergely Karácsony is the head of Dialogue for Hungary, which is the Hungarian green party, and he has been an environmental advocate for several years [6]. Karácsony emphasized the importance of participation in his electoral program, in which he claimed that the basic interest of the local government dictates that it should be addressed to the people of Budapest in as many areas as possible-be it community planning, involving the people of Budapest in the implementation of projects, or placing them in community care. In November 2019, the Municipality of Budapest declared a climate emergency, which resulted in the creation of a citizens' assembly in the autumn of 2020 in collaboration with the NGO DemNet. The aim was to identify what Budapest inhabitants should do to address the climate emergency.
The remainder of this article is structured as follows. The second section uses evidence from the literature to identify potential drivers to initiate the citizens' assembly. The third section briefly presents the research design with emphasis on the case selection, methods of data collection, and methods of data analysis. Next, we briefly describe the Budapest Climate Assembly. The fourth section includes an analysis of the factors that led to the emergence of this Assembly. The conclusions summarize the main findings and discuss avenues for further research.

Citizens' Assemblies on Climate Change
Citizens' assemblies are a form of deliberative mini publics that include a randomly selected body of citizens to reason together about an issue of public concern. They originate in the 1980s and emerged at the margin of the political system, gaining attention in the 2000s [7,8]. Citizens' assemblies aim to make recommendations to political leaders and illustrate how decision-making can follow an inclusive process of discussion considering all perspectives carefully in light of evidence [5]. For example, the Canadian assemblies on electoral reforms provided recommendations directly to the public at the regional and national level [3]. Similarly, Irish assemblies make recommendations on polarized constitutional issues such as same-sex marriage and abortion [9].
Gradually, an increasing number of central government institutions have started using citizens' assemblies in the decision-making process. In some instances, there are initiatives to institutionalize citizens' assemblies [10] in different forms. For example, to avoid politicians' tendency of cherry-picking issues and recommendations [11], some activists proposed radical propositions to create a new chamber in parliaments composed of randomly selected citizens [12].
In the field of climate, citizens' assemblies are organized to address the challenges in a particular way [13]. Through the prioritization of the commons over self-interest, the 'talk-centric' deliberative approach of citizens' assemblies can lead to support for ambitious climate policy solutions [14]. For example, the Irish Constitutional Convention discussed nine policy areas including climate change [4] and the Assembly participants decided on 13 policy recommendations that were 'significantly more radical than many expected' [15]. In October 2019, as part of Great National Debate, the French President invited 150 citizens to formulate proposals to fight against climate change. Discussed and amended during an eight-month deliberative democracy process, participants came up with 149 proposals [16]. In June 2019, the UK Government and Parliament passed a law committing the UK to reaching net zero greenhouse gas emissions by 2050. Commissioned by six select committees of the House of Commons, members of the Climate Assembly UK agreed to twenty-five underpinning principles and 50 recommendations for policy measures for achieving a balance between the amount of greenhouse gas emissions produced and the amount removed from the atmosphere [2].
While nation-states have struggled in recent years to work collectively and sometimes individually to mitigate climate change, sub-national units such as regions and cities emerged as important sites of climate policy innovation. Earlier studies argue that the response to climate change globally can be best observed if we pay attention to sub-national government climate actions [17]. When it comes to climate policy innovations, underlying economic motivations, awareness of climate change, and political motivations also shape the decision-making processes [17].
In general, participatory democracy can play an important role when it comes to climate justice education. Climate activists view education as an extension of systemic change and propose different approaches that include "recognized agency and the politics of knowledge production as climate justice issues . . . through participatory democracy" [18]. These studies offer relevant insights into the functioning of these assemblies and their potential to impact decision-making across different contexts. However, they do not allow for comparative investigation of why citizens' assemblies are established. In the next section of our literature review, we focus on main actors behind the inauguration of such assemblies and decisive contextual factors behind the process.

Why Citizens' Assemblies?
This section identifies the reasons leading to the emergence of citizens' assemblies in different policy fields across the world. Starting from the highest level of generality, deliberative practices are often used by political parties with several goals in mind. One of these is the possibility to provide people with genuine deliberation, characterized by importance given to people in the decision-making process, communication and learning processes. Another possibility is the use of deliberative practices by political parties to their own advantage: creating leverage in the political negotiation with other parties, improved communication with the electorate, or greater visibility that can lead to higher electoral support [19]. The instances in which deliberation has been initiated with manipulative purposes are limited mainly to intra-party processes [20,21].
When comparing three citizens' assemblies on electoral reform (two regional assemblies in British Columbia and in Ontario and one at the national level in the Netherlands), Fournier and his colleagues [3] identified three reasons why they were created. First, politicians campaign on the promise to support citizens' assemblies to boost their chances of winning an election. In British Columbia, Campbell, the leader of the Liberal Party, had promised to organize a citizens' assembly when running for office. After being elected as the new premier, he was centrally responsible for its establishment. In Ontario, the citizens' assembly was a politician's initiative where premier McGuinty followed Campbell's example. In the Netherlands, the minister affiliated with the D66 (Democrats 66) political party resigned due to the lack of support within the coalition for his legislative proposal to change the electoral law. Searching for a way to change the electoral system while strengthening the image of the party, his successor came up with the proposal to organize a citizens' assembly. The plans were reluctantly accepted as the cost of keeping D66 in the coalition.
Sub-national governments in areas with a powerful sense of territorial distinctiveness often seek to intensify that uniqueness and to maximize and enhance their political autonomy. Scotland's devolved institutions are relatively new, but they supply political representation for a historic and distinctive nation within the UK. The Scottish case best illustrates the enduring importance of institutional, fiscal and policy capacity but also the ways in which actors can overcome constraints by the proficient use of policy networks, skillful navigation of the multi-level policy environment, and by emphasizing its nonconstitutional and natural energy resources. The case confirms that pioneering action is also driven by economic advantage and the exploitation of economic opportunities according to environmental principles, but economic motivations are certainly more evident than 'green' ambitions within the Scottish case [22].
Beyond the already discussed strategic promises or behaviors, there is also the possibility of ideological match between political parties and the deliberative function of a citizens' assembly. In this sense, the entry of the Green Parties within the government coalition of the two regions in Belgium were a decisive push for the promotion of deliberative tools. These parties convinced their coalition partners to establish deliberative processes [23]. The network of activists that emerged in the second phase played a crucial role in initiating citizens' assemblies at different levels of government and political actors were gradually convinced.
In Europe, most frequently left-wing or green parties initiate participatory democratic actions [24]. In the case of Belgium, political parties that are in favor of participatory democratic innovations are post-materialist parties who "share a cosmopolitan vision of society" [25]. These parties underline the fact that the increased participation of citizens in the processes of public policymaking favors an investment and a renewal of citizens' interest in politics.
Green parties have reformed their own internal organizations to be more inclusive and advocate for larger scale democratic changes. Due to their pioneering role, some claim that green parties represent democratic issues most effectively, and most importantly, they are the most competent and credible delegates of these concerns: "The German Green party argued that political work should not be just confined to the representatives. Instead, it should also be considered as a citizens' job" [24]. While participatory democracy is present in green party manifestos, deliberative democracy appears less. In the case of Belgian green parties, there are two aspects in which the parties advocate for deliberative democracy: to revitalize and irrigate the representative system and to create real local deliberative assemblies.
According to the two Belgian green parties, participatory democratic implementations can strengthen and re-establish the links between citizens and the political authorities and also improve the legitimacy of public decisions. However, it has to be noted that in Belgium, parties that are most in favor of participatory democratic innovations (referendum, popular consultations, etc.) are anti-establishment far-right parties [25].
Against this backdrop, building of a territory's political identity can also be an important motivation of the German-speaking community of Belgium behind creating a permanent citizens' assembly. In this case, the subtle connections between the citizens' assembly and the local German community can be explained by the socio-political features of the minority group and by the fact that the aim of the assembly was to support identity building [10].
Another study suggests that the level of citizens' capacity to understand and contribute to complex policy issues can be an obstacle when planning to organize a climate assembly. To this, we can add two other potential obstacles: how politicized and adversarial the issue of climate change is, andthe role of the media in citizen assemblies. Even though technically the citizens are in charge, their destiny is in the hands of key elites. Accordingly, "processes such as the CA need to be designed, understood and communicated as part of a broader consultation program" [26].
The Irish Citizen Assembly is a highly praised deliberative democratic innovation that was able to response to the climate crisis. In 2011, Irish academics ran a pilot citizen assembly with the premise that such events can connect Irish citizens to politicians and increase their democratic participation [27]. From 2013 to 2014, this forum "deliberated on potential changes to the constitution that could then be put to a wider population in a referendum" [27]. Climate change became a topic of the assembly in 2017. According to Devaney et al. [27], Ireland was famously disappointing when it came to climate change, as local civil society groups called Ireland "climate laggard" and not without reason as the country "repeatedly ranked as the worst performing EU member state in the annual Climate Change Performance Index" [27]. The Irish case demonstrates the importance of citizen climate assemblies as it presents how governments can become more inclusive and collaborative when including citizen opinions in the decision-making processes. However, deliberation is only one form of public engagement that must be combined with other sources, such as education or communication, but in the proper context, "citizens' assemblies can facilitate societal buy-in for tough policy decisions by including the concerns and ideas of citizens in policymaking, increasing the legitimacy of decisions and actions taken. For citizens, they can represent a unique learning environment and help to re-connect the public with democratic processes" [27].
This set of studies give some hints about why (or why not) citizens' assemblies are created in different contexts, but they do not rely on a systematic empirical inquiry. In order to present the diversified reasons behind citizen assemblies, we collected the emerging factors and compared them in the case studies (see Table 1). This theoretical section indicates that citizens' assemblies remain top-down processes. There are several drivers behind the creation of assemblies that will be closely investigated when turning to the Budapest case. Our analysis seeks to understand which of the factors outlined in Table 1 favored the establishment of the Budapest Climate Assembly. In this sense, we distinguish between the political interest of the promoters, their ideology, the creation of a local identity, the pursuit of a broader economic interest for the community, and environmental sustainability.

Research Design
Our analysis focuses on an influential case [28] from Central and Eastern Europe where political parties often lack stable connections with local associations [29]. We focus on Hungary because it has a political system in which both the relations among parties and the relationship of the party system with its environment is affected by populist polarization [30]. Hungary has some experience with direct democracy but the spread of democratic innovations to complement the institutions of representative democracy is limited. As such, the country is the least likely case in which citizens' assemblies are expected to be convened for community decisions. In particular, Budapest contributes to these characteristics due to its local government that opposes the central government. Such a situation would expect the political fight to be on the agenda at the expense of citizens' involvement in the community.
To understand the reasons behind the establishment of the citizens' assembly, we use a combination of document analysis and semi-structured interviews. The documents consist of the election manifestos used in the 2019 municipal elections and the climate related policy documents (e.g., the draft of the climate strategies of Budapest), and documents that were circulated to invite citizens to take part in the process. To complement the information from these documents, we conducted six semi-structured interviews with politicians and experts involved in the process: the Mayor of Budapest, the Deputy Mayor, the advisor to the Mayor, one city councilor in charge of the process, or the main organizer from the NGO in charge, and one facilitator. The face-to-face interviews were conducted in June-October 2020 (Appendix A).
The interview guide included eight main themes: the role of the interviewee in relation to the citizens' assembly, the interviewee's understanding of the context and purpose of the assembly, reflections on the content and structure of the assembly, reflections on its practicalities (accessibility, structure), reflections on how the process enabled or hindered participation, the assembly's impact on climate change, and expectations on outcomes from the assembly. To analyze the content of answers to interviews we used narrative analysis [31]. The aim was to achieve an understanding of complex phenomena by explaining the richness and complexity of a real setting [32].

An Overview of the Budapest Climate Assembly
In November 2019, as one of the first measures of the new city administration, Budapest declared a climate emergency, which was in line with the approach of many other European cities [33]. In the summer of 2020, the Municipality of Budapest invited the public to discuss how to deal with the climate emergency. This commitment to community planning that involve citizens was novel because it relied largely on the participation of activists and experts. Although the Citizen's Assembly on Climate Change was commissioned by the City Hall, the congregation process was not designed for their political needs or expectations, but it was developed by civil society members [34]. It was organized in September 2020 and invited 50 randomly selected citizens to better understand the issue of climate change from politicians, experts, and leaders of different NGOs, and to suggest potential solutions for the Municipality of Budapest. The community meetings were coordinated by the DemNet Foundation for Development of Democratic Rights with the participation of several civil society experts and with the support of the British Sortition Foundation, the European Climate Fund, and the Municipality of Budapest.

Selection Process and Participants
In August 2020, 10,000 residents of Budapest received a personal invitation to the Climate Assembly. The names and addresses of the guests were requested by the Budapest Municipality from the address register of the Ministry of the Interior within the framework of group data provision. From the hundreds of respondents in Budapest who responded to the invitation, DemNet Foundation had already randomly selected 50 people who were over 18 years old and reflected the population in a way that was representative of age, gender, education and place of residence. The people could indicate their intention to participate on an online interface. During the registration, applicants could ask Budapest Municipality for help by phone or in person via customer service. During the registration process, in addition to their contact information, applicants were required to provide their education as well. Due to the COVID-19 pandemic, the recruitment began later than planned, which presumably reduced the response rate. During the second step of the selection process, DemNet compiled a list of 50 participants who represented the population of the capital over 18 years of age by gender, age, education, and place of residence, in a representative random selection of applicants. Due to the pandemic, many withdrew or did not show up in the last few days before the first weekend of the Assembly and due to the shortness of time the organizers were not able to replace them. As a result, a total of 39 people attended the Budapest Climate Assembly [33].

The Organizers, Process and Topics
The citizens' assembly was organized in two weekends (16-17 and 26-27 September 2020). Two senior experts were responsible for the professional program of the Climate Assembly. The experts are recognized for their knowledge on the topic discussed at the Assembly weekends; they have thorough insight into the topic from both mitigation and adaptation perspectives, are familiar with other experts in the related fields, and are committed to an objective and comprehensive information sharing [33]. The lead experts in cooperation with the lead facilitators compiled the professional program of the Assembly, coordinated the work of the experts and interest groups speaking at the meetings, participated in the development of the program and were present during the weekends. The events were led by two senior facilitators, with the help of a total of eight trained, independent facilitators working to ensure that the work proceeded effectively and according to a pre-planned process. Table 2 highlights the topics, meetings and the output of the assembly. During the first weekend (16-17 September), experts from different areas of climate change and other stakeholders (e.g., activists of Fridays for Future) gave factual presentations to the participants about climate change and its effects. The presentation topics included the meaning of climate change, opportunities to reduce household emissions, transport and climate, and social adaptation. The participants worked in small groups assisted by trained facilitators in continuous collaboration with each other. During the second weekend, the participants developed 21 proposals on how the Municipality of Budapest should respond to the climate emergency. At the end of the third meeting day (September 26), the participants selected the proposals they considered the best out of the 21, which were later discussed in detail the following day. Finally, members of the assembly weighed the pros and cons of eight proposals, gathered other considerations for the proposals, and voted on the extent to which they supported the joint deliberations [33].

The Drivers for Budapest Climate Assembly
The document analysis reveals the environmental sustainability and economic development of the area as crucial drivers behind the formation of Budapest Climate Assembly. From the sustainability dimension, the environment program for 2017-2021 drafted by the City Council indicates strong policy motivations. The document states that the cause of climate change is rooted in current human activities [35]. Based on that assessment, most of the environmental reports for the city [36] explicitly identified air pollution as one of the major problems with an impact on climate change. The air quality is influenced primarily by the emissions of domestic heating and from transport. Road traffic grew by an average of 1-1.5% per year between 2014 and 2019. According to the report, in comparison with other European large cities of similar size, Budapest is moderately equipped with green surfaces for public benefits and degraded green spaces currently do not fulfill their recreational and conditioning role. Based on these documents, the City Council took several policy measures: it approved the development of green surfaces through the Budapest Green Infrastructure Concept, it declared a climate emergency, and it created a carbon neutrality plan.
The Budapest Climate Assembly was convened as a continuation of the carbon neutrality plan with the aim of contributing to the new climate strategy. The assembly was intended to complement the three institutional measures described above. It aimed to gather public opinion and involve citizens directly in the matter of environmental sustainability that is directly derived from human activity. The set-up of the assembly was the practical component of the initiative taken by the City Council that was encouraged by the activist profile of many people in Budapest. For example, in September 2019 during the third global climate strike, thousands of protesters marched on the streets of Budapest. This was followed by many citizens becoming active online. Both events were covered extensively by the media and had a social impact that was comparable to other European cities where similar events took place [37]. As such, the establishment of the Budapest Climate Assembly followed an increase in citizens growing highly interested in the topic of sustainability.
There were also economic reasons behind the assembly's set-up. These reasons are related to the European Union's (EU) Green Deal that was created for its climate protection efforts, which sets out the necessary economic steps for member states. The Green Deal is an integral part of the European Commission's strategy to implement the United Nation's 2030 Agenda and the sustainable development goals [38]. The EU expects its member states to have an overall climate-neutral economy by 2050, to replace the use of natural gas entirely and to ensure that transport is entirely electric. To this end, Hungary requires around HUF 50 trillion, which is the equivalent of approximately 140 billion € [39]. The Municipality of Budapest relies heavily on EU financial support for climate protection actions, which is not surprising given the extensive budget of the European Green Deal and the political circumstances in which the Mayor belongs to a party that is in opposition to the central government. The planned Climate Strategy and Sustainable Energy and the Climate Action Plan of Budapest indicate the EU and the EU tenders as the main sources of funding [40]. By adapting to EU standards, the local government in Budapest sets a climate strategy that can be implemented with European funds. Once this priority was in place, the Budapest Climate Assembly was a natural step forward.
A close look at the main political actors involved in the process indicates a combination of election pledges, ideological match between the topic of the Assembly and attitudes oriented toward citizen participation. The current mayor of Budapest was elected after two rounds of primaries. The primaries forged unity among the fractured opposition parties and gained their support for his program. His manifesto promised that in case of major investments and developments, he would use the tools of community planning [6]. Unlike other Hungarian politicians, Karácsony devoted a whole chapter on climate protection in his program, in which he discussed several environmental issues such as energy efficiency, zero carbon emission, and ecological cultural shift. Since the Mayor belongs to a party that has environment at its core, there is high ideological consistency between the party's goals and his manifesto.
There are reasons to have the citizens assembly go beyond election pledges and ideological matching. The Mayor appears to believe in democratic innovations as a key tool to address the needs of the community. The report drafted about the meetings of the Budapest Climate Assembly presents the speech delivered by the Mayor to the audience during the opening session. The Mayor explicitly outlined the importance of such tools to address an important policy dimension: "The issue is climate change, which we hear and talk a lot about, but we may still not understand exactly the extent to which it poses a threat to us and to future generations. The tool we use is democracy" [33]. His strong commitment to the process was also reflected in an interview conducted with the Mayor. His emphasis on the importance of citizens' involvement reflects a participatory approach that the Mayor promotes: The logic of participation is that it is insatiable. When you open a door, people come in through it and then they do not want to go out anymore. This is why participation should be expanded continuously, which is why I think we need to proceed in careful steps (Interview 2).
The Deputy Mayor of Budapest in charge of smart city projects promised in his manifesto to involve the widest possible range of society in urban decision-making as much as possible and named community budgets as a means of facilitation (Momentum, 2019). After being elected, the two city leaders remain committed to their electoral pledges. As part of the annual budget, the citizens' assembly process is controlled by the Mayor or a designated Deputy-Mayor. Beyond electoral pledges, another reason for supporting the Budapest Climate Assembly is that the City Council consists of several newly elected councilors who experiment with democratic innovations to increase their party's local embeddedness through networking.
The report written about the meetings of the Budapest Climate Assembly presents the speech delivered by the Deputy Mayor in which he expressed the reason for organizing the deliberative event: We will now talk about a very complex issue: what to do with climate change in general, and how we can reduce its effects here in Budapest. Experts also have an opinion on this, but it is very important that we try to get the opinion of the people of Budapest on this as well [33].
This orientation toward people and the willingness to go beyond representative politics is also reflected in the interview conducted with the Deputy Mayor. He emphasized once again the importance of public voice in the decision-making process not only in the context of the Budapest Climate Assembly but in general: As a city leader I do not sit behind thick walls, but I go to meet people, I put my skin and my arguments in the game, I talk face to face with those whose fate is concerned. In an effort it also means that I try to convince the officials working here to go and talk to people too, to have interaction between the office and citizens (Interview 1).

Civil Society and Political Institutions
The interviews reveal a nuanced picture in which the initiative for the citizens' assembly belongs to the civil society. It was a two-step process in which the NGOs started by deciding the content of the deliberative practice. One of the main organizers explains that two NGOs-DemNet from Hungary and the Sortition Foundation in the UK-played a crucial role in the event. Unlike many cases in which political institutions initiate the deliberative process and invite non-political organizations to coordinate it, the Budapest Climate Assembly had a reverse scenario. The Sortition Foundation won an international grant to organize a citizens' assembly in Hungary, it contacted DemNet as a partner to coordinate and facilitate, and both civil society organizations had to look for a municipality that was open to collaboration. They received "a positive response from the Budapest City Council because they are dedicated to increasing deliberative and participatory methodology in their work" (Interview 4). Using a citizens' assembly for decision making was important for the NGOs because it tries to promote an alternative approach to decision-making: "we try to achieve some sort of multiplication, to invite observers from other municipalities, so they can see that it works well in any given issue, and to hopefully hold more of these CA-s" (Interview 5).
The interaction between civil society and political institutions created favorable momentum for the deliberative practice. Nevertheless, the topic was chosen by the funder, the organization that gave the grant to the Sortition Foundation, as acknowledged by two interviewees working in two different departments in the City Council. One of the interviewees explained that the topic was relatively open for discussion and steered toward "climate change since the funder had a very strong request that climate change as such should appear at the meeting" (Interview 6). The same issue is confirmed by another respondent who provides a detailed picture: "I think there was a limitation in their funding . . . the limitation was that it needed to be around climate issues, but it was kind of flexible. So, there was a time when we were discussing talking about traffic in Budapest and other related topics, but then we decided to go for a more generic question, which climate emergency and the question what Budapest should do about it". (Interview 3) The second step is the one in which political institutions react to the proposals of civil society organizations. In doing so, they use the initiative to fit their general approachoutlined in the previous sub-section-and pursue specific goals. The timing of the event was set according to the policy needs of the City Council: "For us, it was important to organize it before the fall of 2020 because the municipality is working on changing or updating the climate strategy" (Interview 6). The deliberative event could serve the specific goal of framing the communication about climate change along the lines of citizens' involvement: "First, we needed it because of the climate strategy, but second I think it is a very good tool for us to frame the conversation about climate change in Hungary [ . . . ] It is something we need to talk to people about" (Interview 3). This approach is in line with earlier findings about the need for citizens' assemblies to be communicated as part of a broader consultation program [26]. There are indications that the communication strategy was effective at least from the political institution's perspective: "We published news statements right after the event, I saw it today in one of the papers, and I was really impressed because those were exactly the messages I wanted to see about climate change" (Interview 3).
Another specific goal driving the establishment of the assembly was the aim to gather public support for the topic. According to the main organizer of DemNet, the aim was to reach out to media outlets. In order to make the event public, the lectures of the invited experts and all materials provided by stakeholders were posted on the DemNet website and on different social media platforms (Interview 4). One respondent explained that the municipality knew the necessary steps, but it wanted people to support the climate change actions and to understand what should be done. The deliberative event was useful for the local political institution to raise awareness around issues and to see how the problems can be addressed. The respondent explicitly argued that all the proposals received from the Assembly had already been covered by previous discussions in the City Council. The politicians knew what had to be done, but the Budapest Climate Assembly was essential to gain general support for the solutions and issues to be addressed (Interview 3).

Conclusions
This article aimed to explain why the citizens' assembly on climate change was organized in Budapest in 2020. We started from several potential causes derived from the literature. Our qualitative analysis confirms some of the earlier findings in the literature. It shows that the Budapest Climate Assembly was determined by a combination of election pledges, ideological match, pursuit of economic interests, and the desire to achieve environmental sustainability at the local level. More precisely, the elected Mayor of Budapest belongs to a party that has the environment at its core. During the election campaign for local elections, he promised to organize participatory events and to address climate change. In addition to these converging factors, the priorities of the local government with respect to environment were strengthened by the possibility of gaining access to European funds. This possibility could contribute to the development of the local community at low costs for the municipality if EU priorities regarding climate change are reflected in policies.
Equally important, the findings complement and nuance earlier conclusions about citizens' assemblies. The emergence of the Budapest Climate Assembly is different from other similar processes in its bottom-up approach. Instead of being proposed by the municipality-with all the above-mentioned goals in mind-it was initiated by two large civil society organizations. The NGOs received international funding and selected the City Council of Budapest because of its commitment to participatory tools of decision making. The two NGOs decided the design and the topic, and following funders' priorities, the city administration used the opportunity to achieve two specific goals that were not gauged by earlier research. The answers from interviews illustrate that the municipality saw the deliberation on climate change as the avenue to convey the message about this specific policy to the broader population and to garner public support for their decisions. This is in line with earlier research that pointed in the direction of increased legitimacy for representative institutions when using deliberative practices [41][42][43]. The municipality hoped that the assembly would have an educative role for the citizenry and could be used as a springboard to communicate the saliency of the issue within the community. Both expectations are characteristics of deliberative democracy [44], which means that representative political institutions have an accurate perception about how this tool works.
The generalizability of these findings is limited to the single-case study covered here. Nevertheless, we believe it can have broader implications for the study of deliberative democracy. At a theoretical level, we provide the bases for an analytical model that can explain the emergence of citizens' assemblies on climate change (and not only) in the future. This is the first systematic study seeking to identify the causes leading to the emergence of such a deliberative practice. The results allow the development of a framework for analysis in which alternative explanations can be tested against each other and causal mechanisms are explored in detail. None of the explanations outlined by our empirical evidence is context sensitive and they can be easily replicated by further studies.
At an empirical level, this case is another example of how deliberative practices can complement the mechanisms of representative democracy. It brings two elements of novelty. First, the identification of new reasons for which citizens' assemblies are formed is a relevant addition to the existing state-of-the-art. Second, we show how the assembly had a bottom-up formation as opposed to the usual top-down process that characterizes other citizens' assemblies. The initial idea about the assembly emerged among local politicians and the political factor was essential in starting a discussion about its implementation. Nevertheless, its implementation is almost exclusively driven by civil society organizations, which took the major decisions from the selection of participants to the topics to be covered. This means that civil society has an effective avenue to promote citizens' engagement in the decision-making process and that political institutions are responsive to civil society initiatives. This is particularly relevant for a salient topic like climate change that can affect future generations.
Overall, our study can contribute more to theory-building and to a lesser extent to theory-testing. One limitation of this analysis is the absence of insights from ordinary participants to the Budapest Climate Assembly or from broader stakeholders, e.g., trade unions, private companies etc. Equally important, we focus on an assembly conveyed to fulfil clear purposes, as part of a broader strategy, which may raise difficulties of comparison with deliberative practices with a loose goal. Further research can build on our findings, address these limitations and seek to test the explanatory model developed to other contexts. One possible avenue is a comparative analysis across several types of assemblies and political systems, to identify whether the determinants identified in this article hold. Such a comparison would allow the isolation of systemic causes such as the type of political system or the ideological positioning of the party in office. Another direction for future studies can involve participants' perspectives. The citizens attending climate assemblies can be asked about what they consider driving the emergence of this deliberative practice. Their answers can be compared with an objective assessment of the causes or what the organizers claim. Such a comparison can shed light on how accurate citizens see the general picture that favors their involvement in decisions that can change their communities.