Cops Don't Like Cameras

Even though it is (and was) LEGAL to record cops, they took violent exception to being recorded. Man arrested while video recording Boston police officers files lawsuit - The Boston Globe

They were arresting his friend, so he thought he would record the proceedings. That made him guilty of questioning their authority to do whatever the damn well pleased.

Friedman, Paulino’s lawyer, said his client was charged with resisting arrest, assault and battery on a police officer, and disorderly conduct in connection with the incident. He was acquitted of all charges in April

The department has since "reinforced" that public recording is allowed under Massachusetts' law. Probably won't help much.