Not to justify what he has done at all but my guess would be CTE. You have to have some serious problems to be able to do that and we know that many, many former (and almost certainly current) American footballers have this problem from years of either undiagnosed or ignored concussions. And this is my own personal conjecture but the fact the doctor he killed had been treating him could also suggest he was having difficulties and maybe saw him as the cause of them. Or as failing to help him with them.How someone can have the ability to shoot a 9 year old and a 5 year old just 'kin astounds me.
Again, not trying to defend or excuse what he has done as that is impossible, just trying to add some possible context. There is a very interesting documentary about former NFL player Aaron Hernandez that sheds some light on this sort of situation.
