

And under those provisions Harry's actions are entirely justified - he is in immediate danger from an attack intended to cause death or grievous bodily harm, therefore he may legally use any amount of force up to and including potentially lethal attacks to subdue his attacker. While this requires us to speculate about what exactly the law is, since we already know British magical law has at least some kind of provision for self-defense then using the self-defense standard of the Common Law (as well as most jurisdictions in the Western world) is the most reasonable speculation we can make. Remember that this is a discussion of whether or not Harry is guilty of manslaughter/attempted manslaughter - i.e., whether or not Harry's actions, under the law, qualify as a crime.A) How is he supposed to prove Draco was trying that? B) Even if he somehow does, how does it justify using a lethal spell when he could've just as easily used a non-lethal one?.Under the law, Harry's actions would be self-defense. Draco was trying to cast an Unforgivable curse on Harry at the time Harry hexed him.

Of course, in that case the story would be over. And what punishment did he receive? Detention! I think he really got away with that one, because for such a felony he should have been suspended from school at least and also faced some repercussions from the Ministry. Sure, Harry didn't know what sort of spell he had cast, but still: if Draco died as a result Harry would have been guilty of manslaughter. Harry used a curse on a fellow student that could have killed him if it wasn't for the intervention of Professor Snape.
