That is, in fact, exactly how some revolutions with good intentions turned into nightmares far worse than the evils they were revolutioning against.

If you’re going to punish someone, you need to prove they did something wrong. 100% of the time. It doesn’t matter if you “already know” and it’s frustrating to have to go through this slow process where they get to fight back. It doesn’t matter if you’re “on the right side” or whatever. That whole thinking needs to go right the fuck out the window, even if it is satisfyingly simple in the moment.

Edit: To bring some specifics to it:

https://en.wikipedia.org/wiki/Reign_of_Terror

https://en.wikipedia.org/wiki/First_White_Terror

And so on. It also happened in China, the USSR, lots of places. The structures of law are fragile and slow, and just executing the person that someone accused of being a former ICE agent is easy. Until someone with a grudge accuses you, or your family...