Sure, but it isn't like most criminals or suspects don't create some form of evidence when they commit a crime. That's generally how they get caught and prosecuted. It would be weirder if there wasn't evidence... And if he wasn't fully mentally intact, it would make even more sense that he wouldn't try to cover his tracks. That's a key trait of insanity. Not all criminals who don't cover their tracks are insane though. I'm just saying there are reasonable explanations that don't require grand and immensely complicated conspiracies that would have to involve many people. I find the conspiracy angle far less likely. At least as I've seen it presented so far. I suppose someone could have helped put him on the path to do it, but that doesn't mean he didn't do it.