This is tricky and I think normally, based upon previous answers I've seen, it depends on the purpose of the question. There are often legit reasons for doing something a little naughty!
For example
How do I hack my own computer to get my files back since I lost my password
is fine, we can see there is no malicious intent.
The question
How do I hack something I shouldn't for the power of evil
should be closed, but definitely down voted. IMO it's off topic, but with the voting system as it is, even if you vote to close it an no one else does, then who cares - that's the power of the SE sites vote system, to ensure the closes are (usually) community based.
We can only act based upon the question and the information they give us. I've learned of some very cool tools/processes which could be very useful for when I build an army of super villains. However, I learned them from simply stumbling upon them... I'm sure if I wanted to find something I shouldn't have access to, then Google would show me a different forum with the detail I would need.