Under current regulations, law abiding citizens are expected to honestly answer a ATF Firearm Transfer Record. Question f. asks: Have you ever been adjudicated mentally defective (which includes a determination by a court,board,commission,or other lawful authority that you are a danger to yourself or to others or are incompetent to manage your own affairs) OR have you ever been committed to a mental institution? Under the current procedures,there is no way to verify a persons mental status.
A law abiding citizen should not be prevented from attaining a firearm or ammo as per the 2nd amendment. However, it is clear that a National Database of mental healthcare treatment needs to be created as a way to have access to mental status information for background checks for purchasing a firearm.