Taser and Conducted Energy Weapons.

It is clear that CEWs are an increasingly prevalent law enforcement tool, adopted to address a complex and challenging problem. The potential for serious injury from a single deployment of a CEW is extremely low. The debate regarding the link between these electrical weapons and sudden in-custody death is likely to continue because their use is often in complex and volatile situations. Any consideration of injuries has to be put into that context. One must also consider what injuries to a subject would result if an alternative force method was used. Furthermore, the potential benefits of CEWs, including reduction in injuries to the public and law-enforcement officers, need to be considered.

Estimating the Risk of Cardiac Mortality After Exposure to Conducted Energy Weapons.

BACKGROUND: Conducted energy weapons (CEWs), commonly known as Tasers, are a reputed nonlethal law enforcement weapon. Nevertheless high profile cases have suggested a causal association with cardiac death but the magnitude of any putative risk is unclear. METHODS: An electronic systematic review of all real world, cohort studies of consecutive CEW cases was performed. "Pessimistic" and "optimistic" previous beliefs about CEW mortality were derived from an unbounded internet search, including case series but excluding the previously identified cohort publications. A Bayesian analysis updated these previous beliefs with the published objective cohort data. RESULTS: Pessimistic and optimist previous beliefs with modes of 1/700 and 1/7000, respectively, and upper limits (< 2.5% probability) of 1/100 and 1/1000, respectively, were constructed. Three cohort studies formed the objective data source and their combined mortality was 1 in 2728 cases or 3.67/10,000 (95% confidence interval, 1/107,751 - 1/490). The maximum a posteriori estimated risks of CEW mortality for the pessimistic and optimistic prior distributions were 5.3 and 2.2 deaths per 10,000 exposures, respectively. The upper limits (< 1% probability of occurrence) of the posterior distribution were 1 death per 408 and 982 CEW exposures for the pessimistic and optimistic previous beliefs, respectively. CONCLUSIONS: Limited available evidence can be used to construct approximate boundaries for CEW mortality risk and suggests that the population risk of CEW mortality is likely small but not negligible. More high quality data are required to refine these estimates and extreme caution must be exercised before applying these population risks to individual cases.

TASER® conducted electrical weapons: misconceptions in the scientific/medical and other literature.

TASER(®) conducted electrical weapons (CEWs) have become an important law-enforcement tool. Controversial questions are often raised during discussion of some incidents in which the devices have been used. The main purpose of this paper is to point out some misconceptions about CEWs that have been published in the scientific/medical and other literature. This is a narrative review, using a multidisciplinary approach of analyzing reports from scientific/medical and other literature sources. In previous reports, durations of incapacitating effects and possible associations of CEWs with deaths-in-custody have often been overstated or exaggerated. Comparisons of CEW effects with "electrocution" are misleading. Clarification of these misconceptions may be important during policymaker decisions, practitioner operations, expert witness testimonies, and court proceedings. Despite misconceptions in the literature, CEWs can still be a valuable tool for law enforcement activities. Scientists, medical professionals, legal advisors, and investigators of police tactics should be aware of these misconceptions.

Use and safety of conducted electronic devices: what is known?

Conductive electronic devices (CED), such as Taser and stun guns, are sold worldwide for use by security services, although they have also been used for self-defence and even for torture. CED are promoted as non-lethal weapons which can potentially save lives. However, there are multiple reports of deaths temporally associated with CED use. These weapons have definite physiological effects in normal volunteers, especially when accompanied by exertion. Medical examiners often report that deaths followed physical encounters which included the use of CED were due to natural causes, excited delirium and/or drug intoxication. These cases present complex situations in which multiple factors potentially contribute to the death, including electric shocks which cause neuromuscular incapacitation, severe pain and anxiety. Public health officials, physicians and hospital personnel need to be aware that individuals controlled with CED are at increased risk of death. We need better recording of incidents worldwide to understand the extent and outcomes of CED use.

Sudden cardiac arrest and death following application of shocks from a TASER electronic control device.

BACKGROUND: The safety of electronic control devices (ECDs) has been questioned. The goal of this study was to analyze in detail cases of loss of consciousness associated with ECD deployment. METHODS AND RESULTS: Eight cases of TASER X26 ECD-induced loss of consciousness were studied. In each instance, when available, police, medical, and emergency response records, ECD dataport interrogation, automated external defibrillator information, ECG strips, depositions, and autopsy results were analyzed. First recorded rhythms were ventricular tachycardia/fibrillation in 6 cases and asystole (after ≈ 30 minutes of nonresponsiveness) in 1 case. An external defibrillator reported a shockable rhythm in 1 case, but no recording was made. This report offers evidence detailing the mechanism by which an ECD can produce transthoracic stimulation resulting in cardiac electrical capture and ventricular arrhythmias leading to cardiac arrest. CONCLUSIONS: ECD stimulation can cause cardiac electrical capture and provoke cardiac arrest resulting from ventricular tachycardia/ventricular fibrillation. After prolonged ventricular tachycardia/ventricular fibrillation without resuscitation, asystole develops.

Cardiac fibrillation risk of TASER X-26 dart mode application.

In view of reported fatalities there are still controversial discussions on whether electronic stun law enforcement weapons can cause cardiac fibrillation. Experimental data are contradictory. Simplified theoretical estimations led to a negligible low risk of 8.10(-7). With a detailed numerical-anatomical model of an adult man (NORMAN) cardiac exposure to Taser X26 high-tension pulses was quantitatively assessed and the fibrillation risk estimated by accounting for its dependence on excited volume based on 3D cardiac exposure patterns. For distance mode and worst case dart hits it could be demonstrated that cardiac exposure can reach the 30% fibrillation risk level. Risk reduces considerably if direct current flow across the heart is prevented. The overall fibrillation risk of Taser application is further reduced by the limited probability of critical hits. However, in agreement with experimental findings it is demonstrated that cardiac fibrillation risk of Taser X26 dart mode application is small, however, not negligible.