I think that any adult who is mentally healthy should have the right to have a gun. When laws do not permit to people have guns we end up only criminals have them and that is not fair.
Gun law in america is so loose that's why wether you are mentally healthy or not you can get a gun. The gun shop has also responsibility for this if they are not too tight on their terms then it's easy for people to get a gun.
You don't know what you are talking about.
The NCIS background check is always done by gun stores. Period.