3.1. Injury-Based Analysis of Common Police PITs
Most of the procedures and techniques described in the manuals examined [45
] originated in martial arts; therefore, they were not specifically developed to control and lock opponents, but rather to knock them out. In addition, the actors used to illustrate some procedures are wearing a martial arts kimono and none of the manuals includes a section on warming up before going into action. This is quite striking since officers rarely have the chance to warm up before an intervention—rather, they usually have to switch from inactive to active within seconds. On medical grounds, they should therefore be trained in alternative procedures and techniques requiring no warm-up in order to prevent unnecessary risks [42
The manuals examined define and describe the risks of causing serious injuries by acting on points of high (red zones in Figure 1
) or even medium vulnerability (yellow zones) but recommend a number of basic procedures and techniques based on striking such points—or even vital zones. For example, some advice hitting the mental region with a straight or hooking punch, or hitting the chin or temporal zone with an open hand. Because these blows typically hit the head or face, they can cause external injuries in the scalp or facial skeleton, in addition to severe concussion, hemorrhage and/or encephalic injuries potentially resulting in serious nerve damage or even in immediate or delayed death. Thus, hitting the temple, where the temporal bone—the weakest among cranial bones—lies, can easily break it and cause an encephalic injury. Therefore, targeting striking this zone is unjustified unless no alternative target exists owing to the high associated risk of very serious damage or even death [2
]. For example, a punch can easily exert a pressure equivalent to 400 kg, which can very easily damage especially sensitive zones such as the face or cranium.
The neck is one other region officers are trained to punch or elbow even though the blow may inflict serious damage to the airways (e.g., a tracheal or laryngeal injury) and/or to vascular (carotid arteries, jugular veins) or nerve structures [9
]. In addition, a blow on the neck (especially one on the side, where carotid arteries bifurcate) can trigger the carotid sinus and result in sudden fainting—or, as noted earlier, even in cardiac arrest and, ultimately, death [34
]. However, updated manuals also describe choking techniques that can elicit a response from the carotid sinuses and result in a vagal discharge, thereby easily damaging bony structures such as the cervical spine. The resulting injury can range from cervical sprain to rib fracture and lead to highly severe damage of the spine cord with very serious consequences in some cases. The neck is therefore another vital region that should not be stricken or pressed as far as possible [16
Other techniques dealt with in the manuals involve blows on the chest or in the abdomen with a front, side, back or circular kick, a kick stamp or a straight or hooking knee blow. A kick in the abdomen can apply a pressure equivalent to 700 kg—or even more if the typical heavy officer boots are worn—and a knee blow up to 900 kg. Therefore, kicking or kneeing the abdomen has a very high risk of causing a very serious injury such as liver or spleen fracture—and its associated hemorrhage—or damage to the kidneys or the lumbar vertebral spine [29
]. In addition, the epigastrium, where the stomach lies, is in the solar plexus, whose striking can trigger a response altering the heart rate and blood pressure to an extent leading to death through hypotension and bradycardia, respectively [31
]. Updated manuals advise elbowing the solar plexus and describe the applicable technique in detail despite its high associated risk.
Similarly, kicking or kneeing the chest can not only result in bone injury but also in severe lung trauma leading to hemorrhage or contusion—or even to a fatal pneumothorax or haemothorax [22
]. Further, a blow in the precordial zone, where the heart is, can result in cardiac trauma, which, in addition to contusion and direct injury, may cause serious heart rate disturbances and lead to commotion cordis, a condition potentially leading to death within minutes [23
]. Based on the foregoing, these techniques should not be applied to the chest or abdomen if their intrinsic risks are to be avoided, and people’s lives and physical integrity preserved.
The manuals also depict throwing techniques aimed at sending opponents to the ground by using appropriate locks or holds to break their balance. Being suddenly thrown to the ground and landing on a hard surface can cause head or spine trauma, and the trauma be worsened by bumping on, for instance, furniture or a curb [49
In addition, there are also descriptions in the manuals for control techniques, which involve dislocating a wrist, elbow or knee in order to lock the individual to be arrested. These techniques are applied to zones of medium vulnerability (yellow zones in Figure 1
). Although the joints acted upon can easily be damaged, the injuries are rarely serious. The manuals, however, fail to recommend application of these techniques acting on yellow zones, and also to emphasize the potential dangers of acting on vulnerable points.
One other procedure worth noting here is that used to arrest people in motion. While the target individual is unaware, the officer walks to him, grabs one of his wrists and uses his other hand to punch the arrestee. Once the individual has been thrown to the ground and placed into ventral decubitus, the officer rests both knees on him to exert pressure on his neck and back in order to lock him. This procedure, by which the officer’s whole weight rests on the arrestee’s, still in ventral decubitus, can also be used for shackling or even frisking. Hitting the face and pressing the arrestee’s neck and face have a high risk of inflicting severe injury or even death, however [2
]. In fact, pressing the opponent’s neck under one’s knee may result in very serious cervical injuries, impair breathing, hinder blood flow to the brain and, ultimately, death, especially if the arrestee’s resists locking with brusque movements [9
]. Likewise, pressing the arrestee’s back or chest may hinder breathing and lead to suffocation. Very similar injuries can result from the officer’s lying aplomb on the back and neck of the arrestee, who should previously have been placed into ventral decubitus. The potential adverse consequences of this procedure include severe damage or even death if the arrestee’s has to bear the weight of several officers at once [27
]. This is, thus, a controversial procedure involving serious risks that officers should be aware of in order to ensure that the arrestee’s can breathe properly, and also so that serious neck or spine injuries are avoided.
Finally, some manuals deal with “pressure points”. These are vital points officers can hit if needed but are best not targeted to avoid irreversible damage. As stated in the manuals, officers should know where pressure points fall; however, they should think of them as targets to be avoided rather than sought. One such point is the temple, which should only be hit with an open hand [3
]. One other point is the trachea, a blow in which may obstruct or even break it and result in death through suffocation—which is why it should only be hit with the V of the hand [18
]. Similarly, striking a carotid sinus can result in a loss of motor coordination and in fainting [13
]. As noted earlier, overstimulating a reflex-triggering zone can cause a vagal discharge and lead to death through cardiorespiratory arrest (especially when, as recommended in the manuals, it results from elbowing of the carotid). A further pressure point is the pit of the stomach, a reflex-triggering zone in the solar plexus that contains the epigastrium and hitting of which has an associated risk of death. Similarly fragile are the liver and spleen, which can be easily fractured and lead to death through hemorrhage [28
]. All these vital points should therefore be avoided because their hitting can easily have a fatal outcome. Based on the numerous manuals and procedures focused on the zones of high vulnerability it can be observed that the rate of serious injuries is pretty high.
3.2. The Principles of Congruence, Opportunity and Proportionality
Based on the foregoing, and on the police’s commitment to preserving people’s lives and physical integrity, all police actions should comply with the principles of congruence, opportunity and proportionality. This requires advising law enforcement officers and private security guards to act on non-vulnerable points (viz., points in the upper and lower limbs excluding the hands, wrists, knees and feet if at all possible) when applying the above-described potentially dangerous procedures in order to avoid unwanted serious injuries.
In fact, the upper and lower limbs contain pressure points whose pressing may cause strong enough pain to render an individual motionless by effect of their being richly innervated. These non-vulnerable points include large muscles such as the femoral quadriceps, brachial triceps or glutei, large tendon insertion zones such as triceps or lateral vast tendon insertions (indicated in Figure 1
) and others such as the anterior tibial edge, trauma of which can be highly painful even in the absence of injury [43
]. Similarly efficient and undamaging is acting on large joints such as the shoulder, which is less prone to injury under locking (e.g., when handcuffing, tying or shackling). Trauma in these zones can result in apparent injuries such as contusion, ecchymosis, rupturing of fibrils, tendons or muscles, and dislocation. Most often, however, the damage is not serious relative to highly vulnerable or vital zones (red zones in Figure 1
]. In summary, opponents should be locked, and arrested if needed, by applying effective techniques to non-vulnerable points. Therefore, law enforcement officers should be instructed in procedures where the use of physical strength is replaced with weight shifts and pain control in acting on especially sensitive zones and breaking the balance of the individual to be subdued.