I note that President Obama is reportedly preparing executive action that would expand the use of criminal background checks for private firearms transfers. This is a bad, bad idea that will lead to all sorts of complications, not least Constitutionally.
David Kopel sums up the problem in a recent report on gun control for the Cato Institute.
As a 2013 National Institute of Justice memo from Greg Ridgeway, acting director of the National Institute of Justice, acknowledged, a system requiring background checks for gun sales by non-FFLs is utterly unenforceable without a system of universal gun registration. For FFLs, enforcement of recordkeeping is routine. They are required to keep records of every gun which enters or leaves their inventory. As regulated businesses, the vast majority of them will comply with whatever procedures are required for gun sales. Even the small minority of FFLs who might wish to evade the law have little practical opportunity to do so. Federal firearms licensees are subject to annual warrantless inspections for records review and to unlimited warrantless inspections in conjunction with a bona fide criminal investigation or when tracing a gun involved in a criminal investigation. The wholesalers and manufacturers who supply the FFLs with guns must keep similar records, so a FFL who tried to keep a gun off the books would know that the very same gun would be in the wholesaler’s records, with precise information about when the gun was shipped to the retailer.
In contrast, if a rancher sells his own gun to a neighbor, there is no practical way to force the rancher and the neighbor to drive an hour into town, and then attempt to find a FFL who will run a background check for them, even though they are not customers of the FFL. Once the rancher has sold the gun to the neighbor, there is no practical way to prove that the neighbor acquired the gun after the date when the private sales background check came into effect. As the National Institute of Justice recognized, the only way to enforce the background-check law would be to require the retroactive registration of all currently owned firearms in the United States. Such a policy did not work in Canada, and anyone who thinks that Americans would be more willing to register their guns than Canadians is badly mistaken.
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After the 2012 Sandy Hook murders, Obama ordered the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) to inform FFLs about how they can perform a background check for private persons who would like such a check. On a voluntary basis, that order was legitimate, but it would be constitutionally dubious to mandate it.
As a practical matter, criminals who are selling guns to each other (which is illegal and subject to severe mandatory sentencing) are not going to comply with a background-check mandate. It would be irrelevant to them. Ordinary law-abiding citizens who sell guns to each other might be willing to take the gun to a firearm store for a voluntary check, provided that the check is not subject to a special fee, that there is no registration, and that the check is convenient and expeditious. The new ATF regulations for private-party sales comply with two of those three conditions; however, the regulations do require that dealers keep permanent records on the buyer and one of the make, model, and serial number of the gun, just as if the dealer were selling a firearm out of his own inventory. The dealer-based system of registration, created by the Gun Control Act of 1968, avoids the dangers of a central registry of guns, but it does have risks: a government that wanted to confiscate guns could simply harvest the dealer sales records.
Proposals concerning universal background checks have fairly strong support in public opinion polls, but those polls are premised on the idea that the check would be applied to the actual sale of firearms. To the contrary, in proposed legislation, the requirement for government authorization (via a background check and paperwork identical to buying a gun) would apply to far more than gun sales. The proposals apply to all firearms “transfers”. A “transfer” might be showing a new gun to a friend and letting him handle the gun for a few minutes.
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This is not “gun control” in the constitutionally legitimate sense — reasonable laws that protect public safety without interfering with the responsible ownership and use of firearms. To the contrary, such grotesquely overbroad laws have the effect of turning almost every gun owner into a felon by outlawing the ordinary, innocent, and safety-enhancing ways in which firearms in the United States are “transferred” millions of times every year.
There's more at the link. Bold, underlined text is my emphasis.
The entire report is worth reading in full. I recommend downloading it (scroll to the bottom for links) to your own computer for use in discussions with others. Excellent material.