Certain criminals (felons) cannot own guns, but giving anyone without a criminal record the right to buy a gun is ludicrous. Insane people who have been institutionalized or on heavy meds shouldn't own firearms and neither should children under the age of 18. Too many psychos have gone to movie theaters and university lecture halls to gun down dozens of people in recent years. The only reason they got a gun was because no one sent the background check lists a red flag.
Just because a respected person has a complete gun record should mean they are perfectly eligible to be able to purchase a gun. For example, if I was working at a Gun shop, and a customer came in who seemd a bit mentally unstable, but had a clean record, I very well would try to fight the idea of selling them a gun.