I'm pretty sure it's a sorry excuse for a peace officer who's gotten away with a lot of crap before who thinks "I gave you an order, peasant, how dare you not obey me!"
One reason I think so:
Police have not identified the officer involved, but his nameplate in the video reads "D. McLaughlin." The Chronicle reports that a David McLaughlin was hired by the police department in 2014. That same year, according to the Bay City News,
McLaughlin was accused in a civil suit of searching a man's car without
cause, then falsifying a police report when nothing illegal was found.
The plaintiff eventually died, and the case was dismissed.
An illegal search ANY lying on a report. He should've been fired for that, but he got away with it. And God knows what other crap he's probably pulled since.
Once read the line "Most cops are not racist, they don't really care about your skin color, they care that you don't wear blue." Unfortunately, that's often the case.
And when they get away with it, the next big problem is set up.