When I lived in San Francisco (early-mid 1980s) I was a bicycle messenger. There was a subset of messengers who cultivated a 'gonzo' image; looked and acted wild, talked about enjoying running down pedestrians, etc. Every now and then one would hurt or at least frighten some little old lady and the police would then talk about 'cracking down on these wild messengers'.
Watching them, though, I noticed that they didn't bother the wild ones. Instead I'd see them pullover some girl who wore a helmet through the day as she worked her way through school. Stuff like that. This -plus a few other chicken-shot incidents- made me come to the opinion that the SFPD had a large number of cowardly bullies in their ranks.
I wonder if they've gotten any better?