“gangsters”
Perhaps something which might be called disassociation probation might be judicially ordered upon conviction for certain crimes such as shoplifting, robbery, extortion, rape, etc.
If a law enforcement officer sees multiple people under disassociation prohibition associating, that law enforcement office might require them to disassociate. If they are seen by a law enforcement officer associating again, they would then all be subject to punishment for any crime any one of them commits.
If they are seen by a law enforcement officer associating again, they would then all be subject to punishment for any crime any one of them commits.