I believe that there has to be a uniform system for allowing the purchase of a gun...throughout the nation, with a nation-wide database to check applicants through. Maybe I'm naive, but, maybe it would help, at least in some of these cases of mass-murder. There is. In all 50 states, one must pass a Federal background check to purchase a firearm from a licensed dealer. The problem is that what is reported to the database those checks are performed against is not consistent. Lack of a background check did not contribute to this tragedy - poor reporting of the shooter's mental problems did.