Sen. Frank Lautenberg this week is pushing legislation requiring all gun sellers to perform background checks on prospective buyers.

The measure, says the New Jersey Democrat, will go a long way toward keeping firearms from the hands of the mentally ill and drug abusers — a topic that’s returned to national prominence this month following the shooting of an Arizona congresswoman.

“While the tragedy in Tucson weighs heavily on the national conscience, it’s business as usual for gun show dealers who continue to peddle dangerous guns without a background check,” Lautenberg said Monday in a statement. “The gun show loophole remains in place today because the special interest gun lobby has scared off legislators from enacting responsible reform. It’s time to put aside business as usual in Washington and start considering the safety of our families over special interests.”

Under current law, licensed gun dealers are required to run background checks to ensure buyers are legally eligible to buy firearms. Felons, illegal immigrants, habitual drug abusers and the mentally ill are among those banned from owning guns. The guidelines apply to licensed dealers in all venues, including gun shows. But unlicensed dealers are exempt wherever they sell, unless they “know” or have “reason to believe” the buyer fits one of the prohibited categories.

The gun lobby supports the exemption for occasional vendors, arguing that private citizens shouldn't be required to perform background checks every time they want to sell a gun to another private citizen. 

Stirring the debate, an undercover investigation revealed Monday that unlicensed dealers at a recent Arizona gun show sold firearms despite red flags that should have prevented those sales. Investigators hired by New York City were able to purchase firearms from two dealers at the Jan. 23 gun show in Phoenix, even after the buyers revealed they “probably couldn't pass” a background check.

“We have demonstrated how easy it is for anyone to buy a semiautomatic handgun and a high-capacity magazine, no questions asked,” New York Mayor Michael Bloomberg said Monday. “This country must take two simple steps to stop more of the 34 murders that occur with guns every day: make every gun sale subject to a background check, and make sure the background check system has all the required records in it.”

Lautenberg's bill would have had no bearing on the Tucson rampage, which killed six and injured 13, including Rep. Gabrielle Giffords (D-Ariz.). The man arrested in that shooting, Jared Lee Loughner, had a history of disturbing behavior and drug abuse, but was able to purchase his arms from licensed dealers after passing background checks — an incident spurring some lawmakers’ interest in the effectiveness of the federal screening system. 

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