Part of why officers like Chauvin and the other three commit misconduct so readily is that they think they can either skirt punishment completly, or face only minor punishment for their actions. Their department may not think their actions are that big of a deal. But decertification, inability to serve in law enforcement again, and even prison sentences... these are the kind of measures that get those kinds of officers' attention, and hopefully the department heads as well.

The idea of not being able to fire a law enforcement official for abusing their authority tells the story pretty clearly. Firing is fine, but depending on the offense, it should be easier to disqualify an ex-official from entering another law enforcement agency in their state, or even the country. Bad police, and officers whose poor training is leading them to become bad police, need to know that there are consequences to their actions, and firmly established limits on their ability to serve in law enforcement.