The below is additional footage to the officer reviewed 79 times.
It shows a female officer confronting him. I'm not sure what she said but it does look in reaction to the male cop pushing the protester.
Hopefully more cops/partners feel compelled to openly check other cops. I can see where this will cause disruption in the police forces across the country and cause major internal "drama". But small price to pay if it reduces these issues (and gets rid of the bad ones).