Factors associated with law enforcement–related use-of-force injury

Abstract Objective Use-of-force (UOF) techniques are used by law enforcement to gain control of noncompliant subjects. The purpose of this study was to assess factors associated with subject and deputy injuries during law enforcement UOF. Methods This is a retrospective study of nonlethal UOF events from January to June 2009 by a single law enforcement agency serving a population of 3 million. A standard data collection tool, which included basic demographic data, the type of force used, subject response, and if there were any injuries to the subject or deputies involved, was used by deputies for each UOF event. Descriptive statistics were used to describe the specific subject and incident details. Univariate and multivariate analysis was used to identify factors potentially associated with subject and deputy injuries. Results There were 1174 UOF incidents recorded during the study period. A total of 282 incidents (24%) involved no physical force, 135 (11.5%) involved less lethal methods, 620 (52.8%) involved other physical restraint methods, and 137 (11.7%) involved both less lethal and other physical methods. Factors with the largest independent associations with subject injury were physical resistance by the subject (odds ratio [OR], 2.65; 95% confidence interval [CI], 1.49-4.74) and force used to prevent a violent felony (OR, 2.15; 95% CI, 1.24-3.71). When the subject had a weapon (OR, 4.15; 95% CI, 1.53-11.23) and physical resistance by the subject (OR, 4.15; 95% CI, 1.24-13.94) had the largest associations with deputy injury. Conclusions This study identifies situational characteristics potentially associated with subject and deputy injuries during UOF events.