While police body cameras are intended to provide transparency and additional insight into what happens during police-involved incidents, a recent study revealed that footage has not been released in nearly 40 percent of all fatal police shootings.

Upturn, a Washington, D.C.-based policy think tank, reviewed more than 100 cases where body cameras were present and found that in 40 of the reviewed incidents, footage was never made available to the public.

In the remaining 65 cases in which the body cam footage was released, it was rarely made available in the immediate aftermath of the incident. In just three cases, the footage was released on the same day as the fatal shooting. The median release time was nine days after an incident occurred. In one-fourth of all cases, it takes police more than one month to release the video.

The longest wait discovered by Upturn was in the case of the shooting of 35-year-old Andrew Byrd in Pueblo, Colorado. The Pueblo Police Department waited 276 days —about nine months—to release footage of the confrontation that resulted in Byrd’s death.

Release of the footage often has to do with local laws regarding body cameras, which vary across the country. Texas requires all relevant investigations to be concluded before footage can be made public, for example. Major cities like Chicago and Los Angeles have multi-week waiting periods that can keep footage from the public for nearly two months.

The reasons for withholding body camera video can vary, but it is often related to the believe that making the footage public would undermine the integrity of the investigation or taint a jury pool by coloring their view of a case, though there isn’t much evidence to suggest that is the case.

In 2017, the New Jersey Supreme Court ruled that video footage of a shooting is in the public interest to release, noting, “[u]nder the common law, the public’s powerful interest in disclosure of that information, in the case of a police shooting, eclipses the need for confidentiality once the available, principal witnesses to the shooting have been interviewed.”

Some media outlets have started to push law enforcement to make footage of shootings available, especially in cases that have public interest. This month, a group of fourteen news entities urged a New York judge to reject a police union's efforts to prevent the release of footage from officer body cameras.

“If we believe that body-worn cameras should shine a light on the most critical cases ....mandatory footage release policies should be considered a prerequisite for every department with a camera program,” the Upturn study concludes.

While body cameras are important for providing insight and context into police-involved incidents, it is not clear that they change police behavior. A study published last year looked at the behavior of police officers in Washington over an 18-month period and found officers equipped with cameras used force and received civilian complaints at the same rate as those without them.