What is the real truth about the TASER conducted electrical weapon (CEW)? The problem with debating this topic is that it has very polarized opinions that are generally based on emotion or anecdote. Either you love it for the technological advances it brings to the practice of human restraint or you hate it for the potential it brings for misuse. Both approaches incorporate rhetoric and underlying agendas when it comes to talking about these devices, and the majority of people will obtain their information about this topic in some type of sensationalized format such as media publications, personal Web blogs, or conspiracy Web sites.1–3 These sources, unfortunately, are prone to errors and personal opinions and do not present objective data with full explanation. Luckily, there also exists scientific literature on the subject, but this is more difficult to search out, can be costly to access, and requires some understanding of statistics and scientific principles to interpret.

The publication of the TASER CEW papers by Vilke et al.4 and Swerdlow et al.5 in this issue of Academic Emergency Medicine add significantly to the growing body of human research on this topic. Critics of the existing scientific literature have maintained that research in this field is primarily funded by the device manufacturer, TASER International, Inc. (Scottsdale, AZ), or that work has been performed with inadequate methodology yielding inaccurate results. There is little doubt that this type of criticism will also emerge since Swerdlow is a member of the TASER International Scientific and Medical Advisory Board, and the study by Vilke et al. did not use subjects who were drug intoxicated, deliriously agitated, or mentally ill (conditions commonly presenting in persons who have bad outcomes following interactions with law enforcement). However, as work in this area continues to grow, those arguments become academically weak. Also, it is important to remember that unexpected sudden death shortly after interaction with law enforcement is not a new phenomenon; there are cases of similar custodial deaths dating back long before the invention of the CEW.6 The CEW is, perhaps, the most intensely studied and vetted law enforcement tool in existence, and the majority of the human work in this area is supportive of its safety profile. Considering what the CEW is designed to be used for, and that the alternatives available to law enforcement personnel likely involve a blunt impact weapon or a firearm, it becomes easier to understand why the TASER CEW should be associated with protecting life instead of contributing to taking it.

The paper by Vilke et al. explores the important variable of exercise in combination with CEW exposure. In 2006, a study led by myself examined a number of physiologic measurements in humans following CEW exposure and did not find a clinically significant change in the measured parameters.7 This work was criticized for using rested subjects because it is uncommon for rested subjects to be involved in a CEW-mediated altercation with law enforcement (these altercations are usually precipitated by significant physical resistance or an exertional foot chase). Because of this, factoring in the component of exercise is an important one. Vilke’s group has demonstrated no clinically significant changes in ventilatory and blood parameters of physiologic stress following a 5-second CEW exposure. This dovetails nicely with recent work by our group that also examined a heavily exerted population following a 15-second CEW exposure and concluded that there was no evidence of worsening acidosis or cardiac troponin measurement.8

The work by Vilke et al. is also notable because it adds support for use of CEWs by law enforcement when interacting with dangerous individuals in compromised physiologic circumstances. Let’s be honest: law enforcement authorities are in the difficult position of having to take control of significantly resistive persons while under intense scrutiny with the public expectation of a perfect outcome. And while training, updated tools, and improved tactics allow for this in a majority of cases, anything less than an excellent outcome creates a situation of potential public outrage. Academically, we can probably all agree that law enforcement personnel have a difficult job to do, and any time a CEW is legitimately used during the course of this work, the stakes are going to be high. This work by Vilke’s group adds to the literature on this topic and offers yet another demonstration of the reasonable safety profile of the CEW. Additionally, the fact that this study was not sponsored by industry limits the popular argument of preconclusion bias.

Although the prospective model of Vilke et al. was limited by the artificiality of the laboratory environment and the relative healthy population selection bias, one could argue that the study was very similar to real-world application from the standpoint that one of the volunteers sustained an unexpected injury (a spine compression fracture). CEWs appear to have a high degree of safety, but like any other law enforcement tool or tactic, when applied to humans, they are not completely without risk. The injury to the volunteer in this case was unfortunate, but speaks to the legitimacy of the testing efforts.

It is also important to note that this work by Vilke’s group marks an important turn in the CEW research journey. Until now, much of the prior CEW research has focused on evaluating whether or not a CEW is capable of causing cardiac arrest by means of traditionally understood electrocution (direct induction of cardiac arrest). The focus of CEW research is now broadening to evaluate other less obvious mechanisms of possible negative interaction. The work by Vilke et al. allows for evaluation of whether or not exercise (and hence exhaustion/acidosis) in combination with CEW application might have a negative physiologic effect. The fact that none was apparent should not be lost on the reader.

Also in this issue, Swerdlow and colleagues provide us with a paper examining the likelihood of CEW exposure yielding sudden death from directly induced ventricular fibrillation cardiac arrest. This concept is significant because there has been controversy in the literature over whether a CEW application is capable of this. Animal work has demonstrated concerning findings in this regard, whereas human work has not.9,10 While interpretation limitations exist for all research work in this area, Swerdlow’s group offers some evidence in support of the CEW rarely causing this in the world of actual field applications. The importance of this may be in adding to the evidence that speaks against the necessity of having a policy stating that an automatic external defibrillator must be readily accessible to any law officer deploying a CEW. A case of ventricular fibrillation occurring greater than 13 minutes after CEW exposure is often used to support this concept.11 However, a reactionary policy such as this would not be supported by Swerdlow’s data. The fact that law enforcement can effectively impact cardiac arrest outcome by having access to an automatic external defibrillator is a concept that appears to be independent of CEW possession or use.12

The work by Swerdlow et al. also uses a remarkable method of research data mining. Unlike national trauma or myocardial infarct registries, no complete or accurate national database on sudden custodial deaths currently exists. Although limited by its retrospective nature and likely far from perfect, the work by Swerdlow et al. is a great example of “open-source” (information source open to the public) data gathering. This mechanism of gathering information is not often used in medicine, but represents a novel way to access data that would otherwise be very difficult to obtain on a large scale. To date, there is only one other project that has utilized this type of methodology to examine sudden custodial death parameters.13 Its conclusions also support the findings of Swerdlow and colleagues. It is likely that research in this area in the future will increasingly utilize this type of data gathering until (and unless) a legitimate and valid national database for this subject exists. Additionally, the strength of this data collection technique lies in its simplicity. The data are what they are. Regardless of the author’s advisory role to an industry company, he is simply reporting what is available to him and not prospectively designing his study to show a specific outcome. This has allowed him to test a hypothesis within certain well-stated limits.

Finally, the work by Swerdlow et al. also supports the shift away from traditional CEW “electrocution” research. The objective was to determine how likely electrically induced cardiac arrest is in sudden death cases following a CEW application. Despite the substantial limitations of the data collection methods, this important work demonstrates that the likelihood of this is rare. This conclusion is also in line with prior human CEW research and lends support for changing the direction of future CEW investigations. If a connection between CEW application and sudden death is to be found, we should be looking to other less traditional mechanisms for this answer.

Although CEWs will continue to be subject to controversy, there has been considerable progress made in researching this topic. The papers by Vilke and Swerdlow and their associates in this issue add to this increasing body of knowledge. As the quest for truth about TASERs continues, these will be important contributions in the future debate.


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