What do we do with the "broken steps"?

Context: a broken step is someone or something within your community which only the locals know to avoid.

Suppose we have a confederation, and someone within the confederation is accused of being dangerous to others in some way. If we kick them out then what stops them from going somewhere else and repeating the pattern? Or coming back for revenge? Or, Stirner Forbid, they're innocent? And even if they are dangerous, is that any reason to turn them away? We make considerations when it comes to wolves and cacti but draw the line at cousins? But they could hurt the community... you see my dilemma.