LOL. What would you do if you had evidence of police misconduct? Take it to the police? Take it to the prosecutor? Take it to a judge?
Unless you can get it into the media you cannot get any justice. From personal experience, even if you take hard documentary evidence of misconduct to the police, prosecutor or judge, each of them will laugh you out of the room.
There are pro-law enforcement groups that brigade YouTube and file bogus complaints, including DMCA violations, against uploaded videos of police misconduct and brutality. If they do it enough, YouTube will even ban the uploaders and take down their videos.
Unless you can get it into the media you cannot get any justice. From personal experience, even if you take hard documentary evidence of misconduct to the police, prosecutor or judge, each of them will laugh you out of the room.
Who watches the watchers?