Yet, nobody arrested.
There was a TV show about SFPD, kinda like Cops.
It showed people getting busted, and then after, included if convicted, etc..
I watched about four episodes, and everyone got off with zero consequences.
What I took away from this TV show was that, basically you can go to San Francisco, deal in heavy drugs, kill five people, rob six places, hijack twelve trucks, carjack twenty SUVs, and go home at the end of the day.
This incident pretty much proves it too. Shoot ten people, and go home.
Their LE agencies seem to be more concerned with hiring gays and lesbians than actually catching criminals and then actually prosecuting them for their crimes. The TV show made it abundantly clear. All criminals in San Francisco are just poor misunderstood victims.