User blog comment:FairyRaven/Fairy Tail Chapter 335: The Time of Life, Review and Commentary/@comment-70.233.144.119-20130614164111/@comment-7418318-20130615071210

To go back up a quite a few posts: I think Minerva is the least likely of all people in the story to join Crime Sorciere, because to get in you must have renounced your "evil ways".

Minerva doesn't really look like she's going to become "good" from being beaten once... rather the contrary. I'd figure her to be someone to seek revenge rather than forgiveness.

As for Naval battle, since it was part of the competition, attacking lucy can't be counted as assault and I really doubt there is a law that says it's forbidden to hit unconscious people.

That Minerva wasn't arrested and was allowed to participate in the last event two days later is pretty clear evidence that she managed to stay within the borders of both the rules of the GMG and Fiore law.