What is the possible use of full auto by a citizen? I typically defend gun owners and their rights in these threads but full auto is my line.

Well obviously his means of use is the most unacceptable. He'll probably be found to have had mental health issues, never should've had a weapon, etc. That to me is the biggest issue, our inability to adequately treat mentally unstable people and also keep them away from weapons. BUT, I don't think anyone should be able to get their hands on a full auto weapon.