Duran had recent back surgery. That's easily verified. And makes it just about impossible to refute pain r/t a forced posture change. The surgeon likely won't like having his work ruined, either. And will probably make a good witness. 

Hopefully, these cops and their supervisors will face large financial penalties and legal fees, if not criminal charges. If the many decent cops won't purge the thugs themselves, then the Blue Wall will have to be torn down from the outside. 

But the real way to reduce crime and police corruption is to end the absurd, failed, and ruinous war on drugs.