WASHINGTON — After weeks of sometimes wrenching debate over gun safety, Congress will begin to consider legislation this week that is likely to include expanded background checks for gun buyers and increased penalties for those who purchase guns for criminals.
The best chance at legislative consensus appeared to rest in negotiations between Senators Charles E. Schumer, Democrat of New York, and Tom Coburn, Republican of Oklahoma, over a measure they have yet to introduce that would expand background checks to nearly all gun purchases. Currently about 40 percent of gun purchases do not require them.
While Schumer and Coburn remain tantalizingly close, Senate aides say, their talks have stalled over a provision that would require records to be kept of private gun sales.
Republicans and many Democrats in Congress have historically opposed curbs on gun ownership, but public pressure to enact legislation has increased substantially since the Connecticut school shooting in December that left 20 children dead. Members of the Senate Judiciary Committee are likely to signal their intentions at a hearing on proposed gun legislation on Thursday, offering a preview of how other lawmakers might vote. The bill-writing process will probably continue into next week.
Senator Harry Reid of Nevada, the majority leader, has signaled that he would give ample floor time to a gun measure, despite his past opposition to bills he perceived as limiting gun rights.
Senator Patrick J. Leahy, Democrat of Vermont, who is chairman of the Judiciary Committee, has said he wants to address gun violence while the memory of the elementary school massacre is still fresh. ‘‘I don’t think it’ll last long,’’ Leahy said about the window of opportunity in a recent radio interview.
President Obama has asked Congress to take up measures that would create a universal background check system for gun sales and enhanced tools to stem ‘‘straw purchases’’ of guns for criminals who cannot pass background checks. He also supports reinstating an assault weapons ban that expired in 2004 and tightening limits on the capacity of some ammunition magazines.
Leahy emphasizes closing loopholes that allow criminals to avoid required background checks and has his own measure — as do Senators Kirsten Gillibrand, Democrat of New York, and Mark Steven Kirk, Republican of Illinois — to increase penalties for straw purchasing and gun trafficking. Law enforcement officials have said they support a crackdown on straw purchases. Senate aides say Coburn, a longtime gun rights advocate, and Schumer, who is seeking to protect Democrats up for reelection in 2014 in conservative states, have worked out over 90 percent of their differences on a measure to increase background checks.
Under current law, people who buy firearms in a gun shop are subject to a background check using the National Instant Criminal Background Check System, which is intended to weed out people with a criminal history or with documented mental health problems. The system excludes private gun sales, and many states have done a poor job of keeping the system up to date.
The Coburn-Schumer bill would strengthen penalties against states that fail to keep their systems current. It would also expand the background checks to many private sales between individuals. Sales between family members would be exempt, and the bill would also have provisions to require more redress for veterans with mental illnesses who are denied firearms, a notion that compelled Coburn to nearly hold up the completion of a recent bill to finance the Defense Department in pursuit of such a measure.
But the two senators are at odds over whether private sellers should have to keep records of gun transactions, as gun stores must. Coburn opposes the move because of a fear among some gun rights advocates that it would be a precursor to a national gun registry.