Cop not wearing uniform comes out of nowhere, doesn't identify himself and violently grabs somebody placing them under arrest for "assaulting a police officer"- I guess his upper arm assaulted the cop's hand when he grabbed it and started yanking on him.

We also get the "stop resisting" schtick while four of them have him shoved up against a wall and he's not moving. I can see US and Canadian cops are sharing notes.

And they do this in front of someone who's obviously filming the whole thing, so they don't even care that the visual record of what's happening doesn't match their stories.