Unless I missed it, no one as of yet has made any suggestions about how to reduce that number. It's just been all ANGRUH AND TEH COPZ SUK DONG chatter so far.
I've only made about these suggestions half a dozen times.
Stop issuing no knock warrants. People think they are being robbed/assaulted when the cops just break down the door and are likely to attempt to defend themselves especially since the cops' usual incoherent screaming is not much of an opportunity to surrender.
Body cameras. That's self explanatory.
Start controlling traffic with cameras the way it's done in basically every other country on earth and limit police confrontations with the general public.
Actually punish cops who hurt or kill innocent people. This is the main thing that causes the anger. If the police cover for a bad cop they are complicit in his crimes.