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Despite clear demonstrations of the ease with which anonymous weapons transactions can occur online — including ties to mass shooting incidents — the issue has been largely sidelined during the political debate.

After all, the "gun show loophole" — the shorthand expression for exempting a number of gun buyers from background checks — is much more than a gun show loophole. The image of two guy shaking hands to finalize a sale in a crowded, well-lit conference hall is misleading. It's also an online loophole, that lets websites conduct or facilitate sales between people with varying levels of anonymity and legal ability to do so. Unlike at a gun show, online buyers don't even need to leave home.

Yet online sales have only played a small part in the current debate over tighter gun legislation. Background checks have been the most contentious component of the policy effort, with compromise proposals consistently narrowing until the expansion included basically only gun shows and online sales. (As we noted earlier, the proposal will likely not pass, despite strong support from the public and majority support from the Senate.) But interest in the subject have overwhelmingly focused on the shows, not online.

In nearly every mention made on the floor of the House and Senate since the beginning of the year, online sales are a secondary consideration for the expansion of background checks. Online purchases made for the shooting in Aurora and at a salon in Georgia last year were mentioned, but those mentions are part of long floor speeches. Mayors Against Illegal Guns, the non-profit founded by Michael Bloomberg which has been advocating for increased background checks, doesn't mention the subject in its ads targeting lawmakers.

In a front page article this morning, The New York Times reported on the extent to which unregulated online sales facilitate access to weapons for criminals. After analyzing more than 170,000 posts at Armslist.com, the paper found a number of cases in which people barred from owning firearms were selling or hoping to buy. For example:

[T]he Times investigation led to Gerard Toolin, 46, of Walterboro, S.C., who is a fugitive from the Rhode Island police and has two outstanding felony warrants as well as a misdemeanor warrant. His legal status bars him from owning guns, but he was recently seeking to buy an AK-47 assault rifle on Armslist and was also trying to trade a Marlin rifle. He posted photos to his Facebook account of an AK-47 he had already purchased, along with a variety of other guns.

There was also Martin Fee, who has a domestic battery conviction in Florida and other arrests and convictions in Florida and New Jersey, including for drug possession, burglary and larceny. He was selling a Chinese SKS rifle on the classified section of another Web site, BudsGunShop.com.

Online sales require the seller to be a "federally licensed firearms dealer," or FFL, in the home state of the buyer. Sites like Armslist do little to enforce that stipulation — nor are sellers always rigorous about upholding the terms of their licenses. In 2011, the city of New York conducted a study similar to The Times'. That study looked at a number of online sites, some of which, like Armslist, only connect sellers and buyers, some of which directly offer sales. It found instances in which people forged FFLs to make sales, and instances in which they apparently broke the law.

"[I]t is obvious that the online market for firearms is vast," the report found, articulating a number of incidents in which online sales were directly linked to crimes: shooting of police officers, the shooting at Virginia Tech, sales to minors. In the New York study, 77 of 125 online sellers agreed to sell to someone who explicitly said he couldn't pass a background check.

The Times also notes that such transactions are rarely prosecuted.

Despite these cases, it appears that prosecutions of people who illegally buy and sell guns on the Internet are relatively unusual. A review of nearly 100 court cases in which federal authorities seized guns over the last year found that in very few instances were Internet transactions the focus of the investigations.

In part, this is a result of the anonymity associated with the sales.

Despite representing one of the most obvious gaps in coverage, despite almost certainly comprising a growing percentage of unregulated sales, little of this information entered the current political debate over background checks. That debate has instead focused broadly on the the limits imposed by background checks, thanks in part to the stronger political organization of gun control opponents. The public wants more background checks. The Senate is apparently not sufficiently convinced. Maybe a stronger focus on an largely unregulated, anonymous network of sales could have made a difference.

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