Trust. Reality dictates it. Bluntly put, I have worked professionally with 100x as many cops as the rest of the Forum combined, and with 100x closer contact than the victims of traffic stops and the occassional uncle/friend of the family who is a cop, including during several years i was a defense attorney.
Are all cops trustworthy? of course not, and i've both prosecuted and represented cops (former and current). There are litterally hundreds of thousands of law enforcement in the country, so there are bound to be bad people. But they are statistically very rare.
The worst problem some individual cops have isn't overzealousness, or overly testosterone-fueled actions. There are a small minority of cops who are guilty of laziness and not following up. The end result is much MUCH more likely to result in the guilty going free rather than then innocent being convicted.
FTR, i can't swear there aren't ANY jurisdictions in the country which are an exception, but having worked with many departments of varying sizes, cops having a "ticket quota" is a total myth.
I guess this is just
nine "bad apples", then.
And in liberal bastion San Francisco, no less! This isn't something you can merely chalk up to ambient racism like the Dothan incident.
(FTR: My SO works in a prosecutor's office. Her opinion of prosecutors has gone up massively as a result of this experience. Her opinion of
cops... has not. Fun fact: apparently they will reject you for the force if you score too highly on the exam. Don't want the enforcers too smart, I guess.)