So it's all good then. 

No in this rp, heroes can kill as long as it's in the line of duty or in self-defense or defense of others. It's regulated though like being in the police. The issue with regards to him killing is that as a magic-user the White Fellowship of Sorcerers made it illegal to kill a mortal with magic unless it's in the situations described above. So he should be fine unless he coldly executes someone with magic but then he'd be in trouble with the law too.