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Police Officers' Perceptual Distortions During Lethal Force Situations: Informing the Reasonableness Standard

NCJ Number
Date Published
Rod K. Brunson, David A. Klinger
This study examined 80 police officers’ detailed accounts of their perceptions of what occurred during 113 incidents in which they shot people, so as to expand empirical data on what actually occurs in a police shooting from the perspective of a "reasonable officer" at the scene, which the U.S. Supreme Court held to be the measure of the constitutional appropriateness of police use of force, deadly or not (Graham v. Connor, 1989).
The single distortion most often experienced by officers in the course of a shooting event was diminished sound, which occurred in 82 percent of the cases; on the other hand, officers perceived some noises as exceptionally loud in 20 percent of the cases. Officers reported experiencing “tunnel” vision in 51 percent of the cases and having a heightened sense of visual detail in 56 percent of the cases. As for time distortions, officers experienced slow motion in 56 percent of the shootings and fast motion in 23 percent of the shootings. The occurrence frequencies for visual and time distortions once firing began were only slightly different from those observed prior to firing. Implicit in the findings of distortion frequencies is that officers often experience multiple sensory irregularities during single incidents of shootings, and these often change substantially over the course of shooting incidents. From these findings, it is evident that reasonable officers on the scene of police shootings are subject to experiencing substantial levels of perceptual distortion both prior to pulling the trigger and as they fire. This suggests that after-the-fact assessments of the appropriateness of an officer’s behavior just prior to and during a shooting must be judged from the perspective of the perceptual and sensory distortions likely to occur when a “reasonable officer” becomes aware of a potential threat of death or serious injury. 3 tables and 27 references
Date Created: January 31, 2009