-WASHINGTON -- The discussion on Capitol Hill over proposed new gun legislation turned on Tuesday to the underlying constitutional issues around which the entire debate pivots.
Scores of families whose loved ones were killed by gun violence -- including some parents of children from Newtown, Conn., the site of a mass school shooting in December -- packed a hearing room here where legal scholars, lawyers, gun rights advocates and others testified before the Senate Judiciary Subcommittee on the Constitution, Civil Rights and Humans Rights about the constitutionality of various proposals now being mulled by Congress, including the reinstatement of an assault weapons ban.
"Some say that all we should do is enforce the laws on the books," said Senator Richard J. Durbin, Democrat of Illinois and the subcommittee's chairman. The senator citied various measures under consideration, including universal background checks for gun sales, enhanced tools to stem the straw purchasing of guns, an assault weapons ban and limits on the capacity of some ammunition magazines. "All of these proposals are common sense," he said. "All of them have strong support among the American public. And all of them are clearly consistent with the Constitution and the Second Amendment."
Lawmakers tangled over the 2008 Supreme Court decision that struck down parts of the District of Columbia's strict gun-control law, particularly the majority opinion that found gun rights "not unlimited."
The interpretation fell along party lines. Senator Ted Cruz of Texas, the subcommittee's ranking Republican, summed up the position of other Republicans in his opening remarks.
"In my view the divide on this issue is fairly straightforward," Mr. Cruz said.
"The focus should be on criminals" and enhancing prosecutor's tools, he said, including possibly adding a new federal statute against straw purchasing, in which people buy firearms for those who are prohibited from doing so; Mr. Cruz called such a statute an idea with "potential bipartisan" support. "At the same time," he said, "we should continue to respect and protect the constitutional rights of law-abiding citizens."
Timothy J. Heaphy, the United States attorney for the Western District of Virginia, was repeatedly questioned on the efficacy of current gun laws, and when asked to weigh in on an assault weapons ban -- which many gun rights advocates believe violates the spirit of the Supreme Court ruling because it bans, rather than limits, a specific category of firearms -- said he believed such a ban passed the constitutional test.
While the topics of the hearing varied from proposed legislation on mental health services in schools to the wisdom of carrying a gun in restaurants, much attention focused around the one area upon which there is an increasing bipartisan consensus: enhanced and increased background checks for gun buyers. Patching holes in the existing laws "are our best opportunity to keep firearms out of dangerous hands," Mr. Heaphy said.
Some Republicans expressed concerns about the wisdom of such enhanced laws. At one point Senator Lindsey Graham of South Carolina seemed deeply miffed that he might have to undergo a background check to buy a gun from Senator John Cornyn of Texas to improve his hunting outcomes.
Others wondered about how effective such laws would be. "Some on our side wonder why raise all this fuss about background checks," said Senator Orrin G. Hatch, Republican of Utah, noting that most criminals buy guns illegally.
But the enduring potential of new background checks was underscored by submitted testimony from Senator Patrick J. Leahy, Democrat of Vermont and chairman of the Judiciary Committee, who emphasized the "need to close existing loopholes that allow criminals to avoid the common-sense requirement that gun sales should be performed with a background check," and made some vague references to violent video games, but was silent on an assault weapon ban.
The hearing came as a backers of new gun laws swarmed into the Capitol to lobby on the issue and attend President Obama's State of the Union address on Tuesday night. Dozens of people affected by gun violence gathered in the afternoon in the Capitol basement in a room named for Gabriel Zimmerman, a Congressional staffer killed in Tuscon in 2011 when a gunman opened fire on former Representative Gabrielle Giffords.
Mr. Zimmerman's mother, Emily Nottingham, was one of several who called on Congress to reform the country's gun safety laws. In an emotional plea, she recalled how her son loved and admired the political process.
"But he was not naive -- he knew government processes are long," she said. "Please don't let us down."
This article originally appeared in The New York Times.