A bipartisan group of senators introduced a new proposal Monday  to stiffen federal penalties for people who illegally purchase firearms for someone else, signaling continued eagerness between Democrats and Republicans to find agreement on legislation to limit gun violence.

Sen. Patrick J. Leahy (D-Vt.). (Melina Mara/The Washington Post)

Senate Judiciary Committee Chairman Patrick J. Leahy (D-Vt.) announced details of the new bill Monday afternoon on the Senate floor, saying that the proposal will help law enforcement officials prosecute gun crimes.

The bill would make the practice of gun trafficking a federal crime for the first time, with penalties of up to 20 years for "straw purchasers," or people who buy a firearm for someone legally barred from doing so — a group including felons and illegal immigrants. The bill also would punish the person who illegally sells weapons to a straw purchaser.

“The practice of straw purchasing is used for one thing — to put firearms into the hands of those that are prohibited by law from having them," Leahy said. "Many are then used to further violent crimes.”

The agreement essentially merges elements of two competing gun trafficking measures: A Leahy bill that included punishments for straw purchasers and a bill cosponsored by Sens. Kirsten Gillibrand (D-N.Y.) and Mark Kirk (R-Ill.) that would punish the person selling the weapon to a straw purchaser.

In addition to Leahy, Gillibrand and Kirk, the bill is cosponsored by Sens. Richard Durbin (D-Ill.) and Susan Collins (R-Maine), who has not previously signed on to gun control legislation. Other Republicans also may sign on to the plan, the senators said.

Collins said she believed the new proposal "can bring all of us together." She noted that people illegally buying weapons are "easily exploiting the weak federal laws to obtain firearms" and that the new bill would help end the practice and punish people with more than "a slap on the wrist, or treating this as if it were simply a paperwork violation."

In an interview, Gillibrand said she expects at least six more Senate Democrats and Republicans could cosponsor the bill.

"It’s entirely targeted to criminals and the criminal sale and the criminal networks," and thus something that moderates wary of supporting new gun laws should be able to support, Gillibrand said.

The gun trafficking agreement comes as another group of senators — Kirk, Charles E. Schumer (D-N.Y.), Joe Manchin III (D-W. Va.) and Tom Coburn (R-Okla.) — continues negotiating details of a bill to expand the national gun background check program. Disagreements remain on the issue of record-keeping for private firearms sales, according to aides familiar with the talks.

The Judiciary Committee is scheduled to begin debating and approving four gun-related bills on Thursday, with hopes of referring them to the full Senate before the two-week Easter recess.

Sari Horwitz contributed to this report.

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