If punishment doesn't work (and it doesn't) then we don't need prisons and jails as they currently exist, nor do we need police as they currently exist. There's no point to improving the police. Get rid of the punishment angle to policing, then give all the non-punishment jobs that police do to people who are far, far more qualified to handle them than the police are. Then you have essentially no police, so there's no need to improve them.