WASHINGTON • United States President Barack Obama aims to tighten rules on gun sales with a series of measures that include wider background checks and new warnings to firearms sellers.
The measures, which were previewed by White House officials on Monday, were to be officially unveiled by Mr Obama yesterday.
They will include new warnings to firearms sellers at gun shows and on the Internet that they could be subject to laws requiring background checks on potential buyers and face prosecution if they do not undertake the screenings.
They will also require sellers to report firearms lost in transit.
The administration is hiring hundreds of workers to modernise the background-check system, so that more checks are completed within the three-day window that licensed dealers must observe before selling a firearm. It is also requesting US$500 million (S$710 million) for new mental health research.
Some notable mass shootings since United States President Barack Obama took office in 2009.
APRIL 3, 2009: 13 killed
Immigrant Jiverly Wong opens fire at an immigration service centre in Binghamton, New York.
NOV 5, 2009: 13 killed
Army psychiatrist Nidal Hasan goes on a shooting rampage at Fort Hood military base in Texas.
JAN 8, 2011: 6 killed
Jared Lee Loughner shoots into the crowd at a meet-and-greet session in Tucson, Arizona, held by Democrat Representative Gabrielle Giffords.
JULY 20, 2012: 12 killed
James Holmes enters a cinema in Aurora, Colorado, during a Batman film and shoots at moviegoers.
DEC 14, 2012: 26 killed
Adam Lanza shoots and kills mostly first-grade children at Sandy Hook Elementary School in Newtown, Connecticut.
SEPT 16, 2013: 12 killed
Navy contractor Aaron Alexis engages police in a gunfight at the Washington Navy Yard in Washington, DC.
APRIL 2, 2014: 3 killed
Army Specialist Ivan Lopez carries out another mass shooting at the Fort Hood base.
JUNE 17, 2015: 9 killed
White supremacist Dylann Storm Roof attacks black parishioners at a Charleston, South Carolina, church.
JULY 16, 2015: 5 killed
Mohammod Youssuf Abdulazeez fires on two military recruiting centres in Chattanooga, Tennessee.
OCT 1, 2015: 9 killed
Student Christopher Harper-Mercer guns people down at a community college in Roseburg, Oregon.
NOV 27, 2015: 3 killed
Robert Lewis Dear enters an abortion clinic in Colorado Springs, Colorado, and starts shooting.
DEC 2, 2015: 14 killed
Married duo Rizwan Farook and Tashfeen Malik attack an office party in San Bernardino, California.
But the expanded background checks would not have blocked the sales of weapons used in the most recent mass shootings, including the attack last month in San Bernardino, California, and the 2012 school massacre in Newtown, Connecticut. Those weapons were bought legally through conventional outlets.
Research shows that few of the guns bought from unlicensed dealers are sold directly to criminals.
A study by the Justice Department found that just 0.7 per cent of state prison inmates in 1997 had bought their weapons at a gun show. In contrast, nearly 40 per cent said they obtained the guns used in their crimes from family members or friends, and 39 per cent said they got the weapons from illegal street sources.
That is supported by a study released last year by researchers at the University of Chicago and Duke University who surveyed inmates at a Chicago jail. They found that it was rare for offenders to obtain guns via formal channels, with just one in 10 saying he had bought the weapon at a store or pawnshop. Some 70 per cent said they got their weapons through friends, family members or street connections, and the guns had regularly passed through multiple owners.
Dr Philip Cook, a professor of public policy, economics and sociology at Duke's Sanford School of Public Policy, who co-authored the study, said: "I would say the President's action in this area is not going to have much direct effect on criminal access to guns." Still, he added, it could indirectly prevent gun deaths by disrupting the supply chain to the underground market.
Mr Obama has acknowledged the limits of what he can do without help from lawmakers. "Although we have to be very clear that this is not going to solve every violent crime in this country... it will potentially save lives and spare families the pain and the extraordinary loss that they suffer as a consequence" of gun violence, he said on Monday.
The White House said more substantial progress could be accomplished only if legislation allowed further gun controls and the collection of additional data.
However, even determining annual US gun sales is difficult as only a handful of gunsmiths are publicly traded and disclose sales.
Attorney-General Loretta Lynch told reporters on Monday that it was "impossible to predict right now how many additional dealers will register".
The moves are all but certain to draw a court challenge, and have already drawn denunciations from Republicans.
Representative John Culberson, a Texas Republican who chairs a key appropriations panel, sent Ms Lynch a letter on Monday warning that he would "immediately restrict" her department's funding if it proceeds with "new restrictions on our constitutional rights".