Research shows officers don’t change behavior

Usually, we behave better when we know we’re being watched. According to decades of research, the presence of other people, cameras or even just a picture of eyes seems to nudge us toward civility: We become more likely to give to charity, for example, and less likely to speed, steal or take more than our fair share of candy.

But what happens when the cameras are on the chests of police officers? The results of the largest, most rigorous study of police body cameras in the United States came out Friday morning, and they are surprising both police officers and researchers.

For seven months, a little more than a thousand Washington, D.C., police officers were randomly assigned cameras — and another thousand were not. Researchers tracked use-of-force incidents, civilian complaints, charging decisions and other outcomes to see whether the cameras changed behavior. But on every metric, the effects were too small to be statistically significant. Officers with cameras used force and faced civilian complaints at about the same rates as officers without cameras.

“These results suggest we should recalibrate our expectations” of cameras’ ability to make a “large-scale behavioral change in policing, particularly in contexts similar to Washington, D.C.,” concluded the study, which was led by David Yokum at the Lab DC, a team of scientists embedded in city government, and Anita Ravishankar at Washington’s Metropolitan Police Department.

After the public uprising in response to the 2014 police shooting of Michael Brown in Ferguson, Missouri, advocates and many police officials turned to cameras as a way to reduce violent encounters and build trust. By 2015, 95 percent of large police departments reported they were using body cameras or had committed to doing so in the near future.

Until now, the most commonly cited study on police body cameras had suggested that cameras did indeed have a calming effect. That experiment took place in 2012 in

Rialto, California, where officers were randomly assigned cameras based on their shifts. Over a year, shifts that included cameras experienced half as many use-of-force incidents (including the use of a police baton, Taser or gun) as those shifts without cameras. The number of complaints filed by civilians against officers also declined — a stunning 90 percent compared with the previous year.

But the Rialto experiment featured just 54 officers, compared with over 2,000 in Washington. Officers in Washington captured five times as many hours of video. The larger sample size and the long-term way the cameras were assigned added to the reliability of the Washington results.

“This is the most important empirical study on the impact of police body-worn cameras to date,” said Harlan Yu from Upturn, a Washington nonprofit consulting company that studies how technology affects social issues.

Why didn’t the cameras change behavior? After all, we know that other cameras change behavior. Public closedcircuit TV cameras seem to lead to a moderate decrease in crime, particularly in parking garages. Traffic cameras significantly decrease speeding and fatal accidents.

One hypothesis is that officers got used to the cameras and became desensitized to them. But the researchers saw no difference in behavior during the initial phase, when the cameras were new. (The researchers also checked the data to make sure officers were turning their cameras on when they were supposed to, and found a very high level of compliance.) Another possibility is that officers without cameras were acting like officers with cameras, simply because they knew other officers had the devices.

An equally plausible explanation has to do with fear: In Washington, police officers are instructed to turn on their cameras whenever they answer a call or encounter the public in a law-enforcement context. The kinds of situations that might lead to civilian complaints or use-of-force incidents are high-stress encounters. When frightened, humans tend to act on automatic fear responses (or, in the case of good police officers in an ideal world, training).

“It’s a lot to ask, psychologically speaking, to not only remember the camera is on but to moderate your behavior,” said Yokum, the head of the Lab DC.

Finally, cameras might have less impact in Washington because the police department there has already had to confront excessive-force problems. After a devastating 1998 Washington Post series revealed that the city’s police department had shot and killed more people per resident in the 1990s than any other police force in a large U.S. city, the Department of Justice entered into a memorandum of agreement with Washington to reform its policing.

Cities that lack such accountability in their police culture might find cameras more effective, under this theory.