STATE HOUSE, BOSTON, MARCH 26, 2019 -  Requiring all private firearm sales in Massachusetts to take place in a federally licensed gun store -- and be run through the shop's background check system -- would close a "dangerous loophole" in current laws, a Natick lawmaker said Tuesday.

Rep. David Linsky said that, while a 2014 state law created an online portal for conducting the required background checks for private gun transfers, federal law restricts private sellers from also accessing the National Instant Criminal Background Check System.

"This is basically a conflict between our existing state law and existing federal law," Linsky said at an American College of Physicians advocacy day. "This is where federal gun laws come into play, and this loophole has the potential to be exploited by individuals who may pass a state background check but not a national one, thus allowing them to purchase a firearm."

Linsky's bill, which he said is modeled on systems used in other states, would require that any private gun sale or transfer happen at the location of a federally licensed gun dealer, who would be responsible for conducting the background check. The dealer could charge the seller up to $25 for each transfer.

Violators would be subject to a fine of at least $10,000, up to 20 years in state prison, or up to two and a half years in county jail.

"It's not necessarily the neighbor selling the gun to the neighbor that we're totally worried about," Linsky said. "We're worried about that, but it's about Armslist.com and the other websites that do it, and it's about gun shows where, quite frankly, you can walk in and there will be hundreds of people there."

Running a national check in addition to a state one would make sure the "most up-to-date records are being used," Linsky said, potentially catching something from a different state that hadn't yet made its way into the Massachusetts system. He said there probably is not a "huge number" of people who would be cleared in a state background check but disqualified in a federal one.

The Gun Owners Action League opposes the bill.

GOAL Executive Director Jim Wallace said private gun owners in Massachusetts are restricted to four transfers in a calendar year, and both the seller and buyer need to have gun licenses, so have already undergone background checks.

"The way I'm looking at a lot of this stuff now is, what problem exists that you're trying to solve?" Wallace told the News Service. "And not a perceived problem, but what problem exists?"

A version of the bill Linsky filed the last session died when the Public Safety and Homeland Security Committee included it in an order for further study.

Linsky's bill this session (H 2092) has 38 cosponsors and is back before the same committee, which has not yet scheduled a hearing on it.