POLICE: Factors affecting injuries. How safe are stun guns, pepper sprays, use of force

Physical force

The findings clearly show the use of physical force and hands-on control increase the risk of injury to officers and suspects. In Richland County, S.C., soft empty-hand control significantly increased the odds of injury to officers, while hard empty-hand tactics increased the risk of injury to suspects. In MiamiDade, both types of force increased the risk of injury to both officers and suspects. In Seattle, use of force increased injury risk to officers but not to suspects, while the overall analysis (of 12 agencies) showed increased injury risk to suspects and especially to officers associated with physical force. This increased risk was large. When controlling for the use of CEDs and pepper spray in the overall analysis, using force increased the injury odds to officers by more than 300 percent and to suspects by more than 50 percent.

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Suspect resistance

Increasing levels of suspect resistance were associated with an increased risk of injury to officers and suspects. The increased injury risk was especially acute for officers. In Richland County, active aggression and threats of deadly force increased the odds of officer injury by more than 100 percent. The odds of suspect injury were unchanged in Seattle with increased resistance levels. These findings suggest that officers, rather than suspects, face the most increased injury risk when suspects resist more vigorously. Pepper spray The findings suggest that, at least for suspects, pepper spray use reduces the likelihood of injury. In Richland County, pepper spray use reduced the odds of suspect injury by 70 percent but did not affect officer injuries. In Seattle, pepper spray use had no effect on injury rates for officers or suspects. However, the overall analysis (of 12 agencies) showed that pepper spray use reduced the likelihood of injury to suspects by 70 percent, which was even more than the decline noted with CEDs. For officers, pepper spray use increased the likelihood of injury by 21 to 39 percent. This finding was unexpected, and more research may help to explain how officers choose to use pepper spray versus CEDs.

CEDs (stun gun, Taser)

Except for in Richland County where its effects were insignificant, CED use substantially decreased the likelihood of suspect injury. In Miami-Dade, the odds of a suspect being injured were almost 90 percent lower when a CED was used than when it was not. Similarly, the odds of suspect injury went down by almost 50 percent when CEDs were used in Seattle. The larger analysis of 12 agencies and more than 24,000 use-offorce cases showed the odds of suspect injury decreased by almost 60 percent when a CED was used. In Richland County, Seattle, and in the larger analysis, Taser use had no effect on officer injuries, while in Miami-Dade, officer injuries were less likely when a Taser was used. Controlling for other types of force and resistance, CED use significantly reduced the likelihood of injuries. CED adoption by the Orlando and Austin police departments reduced injuries to suspects and officers over time.

Demographic characteristics

Apart from officer force and suspect resistance, few other factors influenced injury outcomes. In MiamiDade, male suspects were twice as likely to be injured as females. The same held true for the 12-agency analysis. In that larger analysis, the presence of a male suspect slightly increased injury risk to officers. In Seattle, female officers were more than twice as likely to be injured as male officers.

Placement of pepper spray and CeDs on a linear use-of-force continuum

People rarely die after being pepper sprayed or shocked with a Taser. However, if injury reduction is the primary goal, agencies that allow use of these less-lethal weapons are clearly at an advantage. Both weapons prevent or minimize the physical struggles that are likely to injure officers and suspects alike. Although both cause pain, they reduce injuries, and according to current medical research, death or serious harm associated with their use is rare. In that sense, both are safe and similarly effective at reducing injuries. Both should be allowed as possible responses to defensive or higher levels of suspect resistance. This recommendation is supported by the findings and is now followed by most agencies that responded to the national survey.

Policy and training issues related to CEDs

CEDs were used far more often (four to five times more often) than pepper spray among agencies that equipped officers with CEDs and were sometimes used at rates that exceeded emptyhand control. Unlike pepper spray, CEDs do not require decontamination and do not carry the risk of accidental “blow back” that often occurs with pepper spray use. However, they do entail the removal of prongs and the potential for an unintended shock to an officer. Even with these concerns, they are rapidly overtaking other force alternatives. Although the injury findings suggest that substituting CEDs for physical control tactics may be useful, their ease of use and popularity among officers raise the specter of overuse. The possible overuse of CEDs has several dimensions. CEDs can be used inappropriately at low levels of suspect resistance. Law enforcement executives can manage this problem with policies, training, monitoring and accountability systems that provide clear guidance (and consequences) to officers regarding when and under what circumstances CEDs should be used, or when they should not be used.

Besides setting the resistance threshold appropriately, good policies and training would require that officers evaluate the age, size, gender, apparent physical capabilities and health concerns of a suspect. In addition, policies and training should prohibit CED use in the presence of flammable liquids or in circumstances where falling would pose unreasonable risks to the suspect (in elevated areas, adjacent to traffic, etc.). Policies and training should address the use of CEDs on suspects who are controlled (e.g., handcuffed or otherwise restrained) and should either prohibit such use outright or limit them to clearly defined, aggravated circumstances. In addition to being used too often, CEDs can be used too much. Deaths associated with CED use often involve multiple Taser activations (more than one Taser at a time) or multiple five-second cycles from a single Taser. CED policies should require officers to assess continued resistance after each standard cycle and should limit use to no more than three standard cycles. Following CED deployment, the suspect should be carefully observed for signs of distress and should be medically evaluated at the earliest opportunity.