Is Vigilante Justice Or Extra Judicial Support Permissible?
Stoping evil by hand or use of physical force is not allowed outside your own domain and even that must be within the permissible limits of the law of the land and social norms. For example, you may spank your kids if they dont follow house rules but it has to be within the social norms. On the other hand you cannot hit your neighbors kids but you can talk to their parents and ask them to manage their kids.
Well what I actually meant is, if we interpret this hadith widely, it became very clear that we can do two more things in our permissible limits: Stopping evil by hand. (Including secretly stopping evil by force) Stopping evil by tongue. (Including secretly providing information to stopping evil) Stopping evil by heart.