Incidence and outcome of prone positioning following police use of force in a prospective, consecutive cohort of subjects.

The safety of placing suspects in the prone position following police use of force has been debated extensively, particularly in the context of sudden in-custody death. The proportion of individuals who remain in the prone position following police use of force is not known, nor has the epidemiology of sudden in-custody death in any position after police restraint been documented. Using a consecutive cohort of individuals in whom police used force, we prospectively documented the number of individuals who were placed in a prone versus not-prone position, and the prevalence of sudden in-custody death in either position. Data were collected for three consecutive years, through a single urban police service, in a city of over 1.1 million citizens. Officers prospectively documented the final position of the subject, among other data points, via electronic study forms embedded in standard use of force report forms. Final resting position was available for 1255/1269 subjects. The majority of subjects are male and demonstrated one or more abnormalities at the time of the event. We found that the majority (57.2%) of subjects were left in a not-prone position; the remainder were left in prone position. One subject died in a not-prone position, no subjects died in the prone position. The sudden in-custody death rate following police use of force was low overall (0.08%, 95% confidence interval (CI) = 0.002, 0.44) and the difference in the proportion of subjects who died suddenly in either position was not significant at 0.14%, (95%CI = -0.8, 0.9). Our results indicate that prone positioning was common and was not associated with death in our cohort of consecutive subjects following police use of force.