For any action to be characterized as "vigilantism" two conditions must be met:

1. The act must be unlawful.

2. The actor must not be a government agent.

Tales of daring-do and complaints of cyber vigilantism should both be viewed with a good deal of scepticism. Much of what is called vigilantism is perfectly lawful, and many of the actors - regardless of the methods they use - are associated with this or that government.