body: I've seen videos of "hackers" on YouTube infecting computers of tech support scammers. If the tech support scammer were to take a program from the person's computer, without their consent or knowledge, but the program turns out to be a virus and once they run it, it destroys the computer of the tech support scammer, is that considered distributing a virus? 
  
  
  And if so, is it a crime if that person's virus destroys a whole system of computers that the tech support scammer works on, even though the virus was taken off the person's computer without their knowledge/consent?
  
  
  
title: Is it illegal to create a computer virus?