As of 2016, 47% of local, county, and state police agencies had acquired body-worn cameras. Larger agencies were more likely to have body-worn cameras; 80% of police departments with 500 or more officers had adopted body-worn cameras, with around 70% of those agencies placing the body-worn cameras in service. Agencies report adopting body-worn cameras to improve training and officer and agency accountability, improve community perceptions, increase officer safety, reduce and resolve civilian complaints, improve evidence quality, reduce liability, and help build better cases for prosecution.[1] Using body-worn cameras as a mechanism to reform practices and policies, however, is less well understood.[2] Interestingly, officers and community members both seem to believe that body-worn cameras help protect them, which suggests incongruence between police and public perceptions and expectations about this technology.[3]

A 2020 review of the empirical literature revealed a proliferation of research on body-worn cameras since a U.S. Department of Justice assessment four years earlier.[4] The impact of body-worn cameras on officer behavior has largely examined two areas: 1) change in complaints against officers, and 2) officer reports on use of force.[5] Some evidence suggests body-worn cameras are associated with fewer community complaints against officers and uses of force, but more citations and arrests.[6] Other evidence suggests uses of force and community-initiated complaints actually increase with the use of body-worn cameras.[7] Some of these variations may be due to structural variations across agencies (e.g., policies regarding use and opinions or definitions on what constitutes force) and less due to behavioral changes by officers. Restricting officers’ discretion in turning the body-worn cameras on and off (i.e., requiring officers to have body-worn cameras on during all enforcement actions) may help reduce uses of force and eliminate a number of community complaints.[8] The high variability in research findings suggests that the impact of body-worn cameras may depend on a variety of agency- and officer-level factors.

Researchers point to how little is known about the impact of various police interventions, including body-worn cameras, on reducing racial disparities in policing outcomes.[9] A national study of local police departments suggests that body-worn cameras do not have an effect on officers’ overall treatment of Black versus White individuals.[10] In another study using computational linguistic methods, researchers found that officers were consistently less respectful to Black versus White persons even after controlling for a number of variables.[11]

As of 2016, 86% of law enforcement agencies that had acquired body-worn cameras had policies for body-worn camera usage and management of resulting footage. Nearly 85% specified the types of events to record; 80–90% required the recording higher-risk events (e.g., traffic stops, officer-initiated contacts, and firearm deployment); 54% covered public release of raw footage, 64% controlled officer review of footage, and 76% had provisions about routine supervisor review of footage. Larger and municipal agencies were more likely to have these policies. It remains unclear how often agencies use body-worn camera footage for investigating potential officer misconduct or for training and supervision purposes. In 2016, the most recent year for which data exists, most agencies received no public requests to view footage on a monthly basis; among agencies with at least one public request per month, 41% of agencies denied access, primarily because the video was part of an ongoing investigation.[12]

Those who believe that body-worn cameras increase transparency, improve police-community relationships, and enhance trust in police are most likely to support the use of body-worn cameras; these beliefs, however, are also affected by pre-existing views and experiences with police.[13] In a 2019 study, researchers found that, although community members generally have high expectations that body-worn cameras will increase accountability and trust, “there are disparities between the legitimacy afforded to the police by various groups, which does not seem to be remedied by body-worn cameras.”[14]

Research reveals that most officers develop more positive or neutral views about body-worn cameras after they use them. Surveys have found that officers see body-worn cameras as protection from unsubstantiated complaints and can help improve the quality and availability of evidence. Some officers use body-worn camera footage to assist with report writing rather than relying on memory alone.[15] Officers’ receptivity towards body-worn cameras is shaped by technological difficulties and the workload of managing devices and videos,[16] concerns about additional oversight resulting in less proactive policing activity (i.e., de-policing)[17], and perceived ineffectiveness of body-worn cameras in affecting community behavior.

Internally, resistance to or support of body-worn cameras appears to have some connection to organizational factors (e.g., police culture, leadership support, policy and procedure, and training).[18] Officers with greater perceptions of organizational justice (i.e., belief that the agency will act in a fair and consistent manner) were more resistant to wearing body-worn cameras. When officers were mandated to wear body-worn cameras (compared to volunteering to wear them), they perceived a larger negative impact on body-worn camera efficacy (i.e., the ability of body-worn cameras to improve policing outcomes such as capturing better quality evidence and more accurate accounts of what happened).[19] Clearly defined objectives and explicit procedures and expectations linked to organizational goals increase the likelihood of successful implementation of body-worn cameras and other technologies.[20] External stakeholder engagement (e.g., community groups, other criminal justice agencies), particularly with regard to policies governing the use of body-worn cameras and the resulting video footage, may also be critical to successful implementation.[21]