I believe every person the first time buying a gun, should be required to have a 1 hour mental evaluation by a psychologist. I really don't think it's too intrusive and it would "weed out" mentally unstable folks and be able to refer them to the help they need. I also think that mental health check should be repeated every few years. I want to say 5, but that could be a little too long. I'd say with every new gun purchase but that's also way too much probably. There's a way to please everyone here and still get the control we need.