Through video footage, those accused of crimes often have evidence that can stand up against police officer reports and testimony. In some cases, it may even catch an officer in a lie.

With many judges and jurors, police officers are often considered the most reliable witnesses to a crime. This makes a cop’s testimony often the difference between a guilty or not guilty verdict. When video exists, however, it drastically changes the dynamic in the courtroom.

“This is a paradigm shift,” said Craig Futterman, a professor at the University of Chicago law school. “The ubiquity of video today has made it impossible for broader society to deny the reality and prevalence of police abuse in black and brown communities. It provides objective evidence of what folks in those communities have already known for years. And now that the jack is out of the box, there’s no putting it back. It’s triggered an ongoing conversation that isn’t going away.”

As cameras become smaller, cheaper and more accessible, everyday citizens can easily record any moment in time, including police arrests, traffic stops and other interactions with the public. These recordings can be monumentally helpful when building a criminal defense strategy. Footage may not always prove innocence, but it can also reveal enough to challenge the police accounts.

In most situations, the video footage may not be easy to find. A defense attorney will have to dig to find witnesses who may have recorded the incident or looking for businesses that may have captured surveillance camera footage.

“We’re the defense, we have to hustle,” said Jeff Adachi, San Francisco’s chief public defender. “These videos usually don’t just pop up out of nowhere.”