I will say this kid demonstrated excellent composure. The only ding on him is that he's underage.
That being said... "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
If I was his lawyer, I would argue that he was part of a well regulated Militia and was providing security in a city that has shown to be incapable of providing security for itself. This is a constitutionally protected right. There's an IG vid where he clearly states that he's doing such. And the vids where he's shoots rioters demonstrates clear cut self defense against people who's intentions were to have the city to burn to the ground.
He was 17 but at the end of the day the constitution > state laws and it's shit like this which was why the 2nd amendment was created to begin with.