The Sunnyvale Police told me to stop taking pictures of the accident while I was standing on my own property. They refused to release the police report of the accident to me (I needed it for insurance claims) because they claimed I was "not a victim and had no right to see it." (The car ended up on my lawn, smashed into my house.)
The only official way to file a complaint against the Police force in Sunnyvale California is to fill out a form and the Police investigate it themselves. Anything else, you have to go to court. There's no independent overseer.
All police forces are rotten to the core, and will do anything and everything to protect themselves.