Police officer body-worn cameras have been promoted as a technological solution to improve police-community interactions. DC police officers wear body-worn cameras as they have been useful for training, resolving citizen complaints, and providing transparency in individual interactions. But do they impact behavior in police-community interactions? Through an experiment with the Metropolitan Police Department (MPD), we found that body-worn cameras had no detectable effect on police use of force, citizen complaints, policing activity, or court outcomes.
Why is this issue important in DC?
When people believe they are being watched, they act differently: cameras can encourage honesty, promote adherence to rules, and reduce crime.1 Given the potential to deter negative behaviors during police-community interactions and provide an important source of evidence, the rapid spread of body-worn cameras across the United States2 is perhaps unsurprising. Yet, body-worn cameras are financially costly and involve new administrative complexities.3
What did we do?
The Lab @ DC collaborated with MPD to learn what effects body-worn cameras have in DC. Between June 2015 and December 2016, approximately half of all full duty patrol and station officers—over 2,200 officers—were randomly assigned to wear BWCs, while the other half remained without BWCs until December 2016.
We tracked outcomes associated with police activity through March 2017, using administrative data to compare documented police uses of force, civilian complaints, policing activity, and court outcomes between the group who received cameras and the group that didn’t.
What have we learned?
We found that wearing a body-worn camera had no detectable effect on police use of force, civilian complaints, policing activity, or court outcomes. These results suggest that we should recalibrate our expectations of body-worn cameras, and specifically the technology’s ability to affect large-scale changes in behavior, particularly in contexts similar to Washington, DC.
What comes next?
MPD continues to innovate and implement new programs to improve police-community interactions including a new training that teaches the history and cultural context of our city. What’s even better is that MPD is taking the same, rigorous approach to evaluating the effects of these new programs.
What happened behind the scenes?
Before we knew the results for this study, The Lab @ DC and MPD presented the program, evaluation questions, and methods to community members across the District, including the Public Defender Service for the District of Columbia (PDS), high school students, DC-area university students, among many others. Discussing our research design—documented in detail and made publicly available in our pre-analysis plan—before we have results is important for transparency and can help mitigate the very natural human tendency to judge an evaluation method based on the results. For example, if you believe body-worn cameras are an important tool for reducing police use of force and the result of the evaluation is positive, then you may think the methods are great, but if the results are negative, then you may think the methods are flawed. Mitigating this tendency helps us have a meaningful conversation on the results once they’re available.
To learn even more about the body-worn cameras project, check out the project’s interactive website.