Very interesting topic. Overall for real world I'd initially say llaw, but vigilantism rises when law is not enough, biased or too lenient. I think it also serves as a good reminder to the state that it is not above the people and they will act up when they don't like the unfair treatment state imposes. So it serves a purpose of reminding the state/institutions in charge of the power people actually have. It's also good for criminals to realise that no, even if you do win the case, that doesn't mean you're now not guilty. It's a fascinating moral question, because of course it can quickly get out of hand and lead to unhinged killings on a much bigger scale. So vigilantism can't go on for long...but it sure would be nice if you knew someone always had your back when the state doesn't, wouldn't it? That there was someone the criminals were actually scared of. For the fictional world...vigilantism all the way! Revenge and vigilantism stories are so so much fun to watch and really feel satisfying. I'm absolutely loving the drama, the only thing I'm sad about is that it's released so slowly and that there are not at least 10 episodes
