First of all, I googled his name and discovered that he had been taken to court over the mishandling of a person on parole. At the time, he was a probation officer. The newspaper has come up with several other accounts that prove lack of sound judgement. Therefore, he should have been removed from duty right away until he was either vindicated or found guilty as charged.
As for due process, he offered none to the handicap man that he punched in the mouth and dragged out of the car.
Power corrupts some individuals--this officer in particular.