Illegal to Film Police?

I read that several states now have outlawed filming police.

The law doesn't seem to make a distinction between interfering with police duties and not interfering.

There have been many cases of citizens filing false claims against the police for brutality, merely as a way to divert attention from the citizens' wrongdoing. As a result, police departments in many areas have instituted a policy of always filming their activities in order to disprove false allegations of brutality.

However, sometimes the allegations are true. And wouldn't the same police officers who act dishonorably also be the ones to have malfunctions with the cameras? For these few cases (overall, but in the areas where they happen they are concentrated) it is necessary for citizens to be able to film the encounter.

Any interference with police duties is understandably illegal, but filming from far away should be allowed. If filming police is illegal in any way and someone captures brutality on film, that person would be afraid to provide the evidence simply because it was a crime to obtain it.

The principle that people are innocent until proven guilty is intended to protect citizens from a dishonest police force. Being allowed to film police has the same purpose.

I absolutely do not condone people who intentionally interfere with legitimate police duties while claiming their right to anything - free speech, right to assemble, or whatever. In those cases, the rights are simply an excuse to do something awful.  Be mindful that it's not the same at all as the reverse - police interfering with people's legitimate right to free speech or right to assemble or whatever.