With the amount of murders by vehicle nowadays, how about every driver check with the Feds when they want to drive then wait ten days to get checked out. No? Well duh. 
You can't expect to rein in everyone because of a one-in-a-million incident. What would turning in spent brass do other than stop someone from reloading. Do you really think that going to gun school and taking marksman classes would have stopped that thug?