Most arrests are discretionary, as the police arrest suspects, not convicted felons. So, what you are really against is unwarranted arrests.
The best way to reduce this is provide compensation for anyone arrested but not charged, or where the case is dismissed, proportional to their wasted time.
Private security companies encompass a huge array of specialities, examples are:
In Britain the police force was nationalised in 1929
Government cannot offer perfect saftey otherwise they would need a camera in every house.
We are not safe because there is a policeman outside everyones doors, we are safe because we are concerned.
Mr. James Duane, a professor at Regent Law School and a former defense attorney, tells you why you should never agree to be interviewed by the police.