Gun control advocates – many of whom really wish they could outlaw any ownership of firearms by individuals – constantly claim new limits are needed to save lives.

But time and time again, violent crime headlines are followed a few days later by revelations that killers would not have obtained guns had existing restrictions been used properly.

Last week FBI?Director James Comey told reporters “heartbreaking” lapses in enforcing the law allowed Dylann Roof to buy a gun in April. In June, he allegedly used it to massacre nine people at a church in Charleston, S.C.

Among failures that allowed Roof to buy a gun was one in which his arrest on a drug charge earlier this year was not taken into account by a federal background checker. That would have disqualified Roof from purchasing a firearm. It appears a paperwork error was to blame.

No doubt the Charleston murders will be used as an excuse for promoting new limits on gun ownership – making life more difficult and costly for law-abiding Americans. Instead, why not put more effort into enforcing existing laws?