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CED-Proximate Deaths
The occurrence of approximately 500 suspect deaths following exposure to a CED since 2001 has raised substantial concern regarding their contributory or causative role in these fatal outcomes. The rarity of deaths following CED exposure, however, makes analyses of these events difficult and expensive (Kaminski, 2009) and, consequently, there have been few related studies.
Bozeman et al. (2009) conducted medical screenings and record reviews of 1,201 exposed suspects. Two CED-proximate fatalities were reported, but on autopsy, it was concluded that the deaths were unrelated to CED exposure. In a similar study, Eastman, Dawes, and Ho (2007) examined 426 exposed subjects and reported one death. This subject, however, had a core body temperature of 107.4F and was intoxicated on cocaine. The remaining subjects in the above studies suffered no or only superficial injuries.
Other medical researchers conducted retrospective mortality reviews, examining hundreds of autopsy and toxicology reports of suspects who died following exposure to a CED. Many subjects were intoxicated on drugs, suffered from cardiovascular disease, or were in a highly agitated state at the time of exposure (excited delirium). In general, these investigators concluded that CEDs are not a common cause or contributor to sudden in-custody death (Kornblum & Reddy, 1991; Strote & Hutson, 2006; Swerdlow, Fishbein, Chaman, Lakkireddy, & Tchou, 2009). Zipes (2012), however, reviewed eight cases of CED-proximate deaths and concluded that CEDs can cause cardiac dysrhythmias and sudden death, although this study was critiqued on a number of methodological grounds (Vilke, Chan, & Karch, 2013).
In a study designed to test the effect of CED deployments on rates of sudden incustody death in the absence of lethal force, Lee et al. (2009) obtained data spanning 5 years both before and after CED adoption from 50 (40%) of 126 agencies surveyed. Controlling for arrest rates, they found that the rate of sudden in-custody death increased more than sixfold in the first full year after deployment compared with the 5-year predeployment average. The authors speculated that high initial rates of CED use contributed to the increase in sudden deaths by escalating some confrontations to the point that officers needed to resort to the use of deadly force. O’Riordan (2009), however, highlighted several design concerns associated with this study, casting some doubt on the findings.
Using a different methodology, White and Ready (2009) conducted a national search of media reports of fatal and nonfatal CED incidents to identify potential correlates of CED-proximate deaths. Using regression and other statistical techniques, their analysis revealed that the number of CED discharges was unrelated to death, alcohol intoxication was negatively related, and both drug impairment and mental illness were positively related to fatal outcomes.
CEDs and Reductions in Lethal Force
Although the focus of research on CEDs has been on their contribution or potential contribution to in-custody deaths (Kaminski, 2009), few studies examined the potential of CEDs to reduce citizen fatalities and the use of lethal force by police (Thomas et al., 2010). Given the deterrent and incapacitative effects of CEDs and other less lethal weapons such as OC, however, it is likely that their early use during some resistive and violent encounters prevents further escalation and the need for the use of deadly force (Mesloh, Henych, Thompson, & Wolf, 2008; Thomas et al., 2010; White & Ready, 2007, 2010) . For example, TASER International reports that as of October 2012, police use of CEDs saved more than 97,000 people from potential death or serious bodily injury. In addition, several law enforcement agencies reported reductions in the use of lethal force by its officers following the introduction of CEDs (Smith et al., 2009), although there have been some exceptions (Amnesty International, 2004; Thomas et al., 2010). However, simple before-and-after comparisons suffer from a number of threats to internal validity and often are not the product of independent research (Alpert & Dunham, 2010; Smith et al., 2009; Taylor & Woods, 2010) . Findings, therefore, must be viewed cautiously.
In a more rigorous study of CED use on mentally ill subjects, Ho et al. (2007) used data on CED deployments self-reported by law enforcement agencies to TASER International and estimated that CEDs were deployed in nearly 50% of encounters in which deadly force would have been justified and that 1,100 lives were potentially saved over a 6-year period because of the availability of the device. A prospective study of 426 CED field uses in a large U.S. city concluded that the availability of CEDs prevented police use of lethal force in 5.4% or 23 encounters (Eastman et al., 2008). Support for these findings was provided by Sousa et al. (2010), who conducted a randomized field experiment to examine differences in responses to lethal encounters between officers equipped and not equipped with CEDs. The results showed that CED-equipped officers were significantly less likely than their non-CED-equipped counterparts to use lethal force.
Although this finding does not specifically address the relationship between CEDs and fatalities, it nevertheless illustrates the potential value of CEDs for reducing officer shootings. Contrary to these results, Lee et al.’s (2009) examination of CED use within 50 of 123 California police agencies found that CEDs were not associated with a decrease in firearm-related deaths. Thus, both the relative paucity of research on this topic and the equivocal findings produced to date warrant additional investigation.
