Even without Congress, Obama could act to restrict guns

* Improvement to background checks tops list of options

* Justice Department has been studying ideas since early

2011

WASHINGTON, Dec 17 (Reuters) - Unburdened by re-election

worries and empowered by law to act without Congress, U.S.

President Barack Obama could take action to improve background

checks on gun buyers, ban certain gun imports and bolster

oversight of dealers.

Prospects for gun control legislation intensified in the

wake of the school massacre in Newtown, Connecticut, as more

pro-gun rights lawmakers said on Monday they were open to the

possibility while Obama and three cabinet members met at the

White House to discuss the subject.

Having just won a second four-year term, Obama does not need

to fear alienating voters who favor gun rights and he could

press ahead without lawmakers on fronts where federal law

enables executive action.

Speaking in Newtown, where a gunman on Friday killed 20

children and six adults in an elementary school, Obama vowed

late on Sunday to "use whatever power this office holds" to try

to prevent such massacres.

"Because what choice do we have? We can't accept events like

this as routine," Obama said at Newtown High School.

His administration has the power to issue executive orders

or new rules, options that Obama is likely to consider in

combination with possible new laws.

The National Rifle Association, the largest U.S. gun rights

group with 4 million supporters, relies largely on its ability

to influence lawmakers in order to block legislation.

Obama's appointees at the U.S. Justice Department have been

studying ideas since the Jan. 8, 2011, shooting of U.S.

Representative Gabrielle Giffords of Arizona and 18 others at a

public meeting. Giffords survived but six people died.

Christopher Schroeder, who ran the Justice Department's

review, said it looked at possible legislation to send to

Congress as well as action the administration could take itself.

"You always look at both, because if you can do it

administratively it's certainly a less involved process," said

Schroeder, who has since returned to a professorship at Duke Law

School.

Many of the ideas have to do with the background checks that

licensed gun dealers run on potential buyers.

CRITICS CITE HOLES

Critics say the system has holes because it does not include

all the data it should on those ineligible to buy guns. The FBI,

which runs the system, could incorporate more data from within

the federal government - using evidence of mental incompetence,

for example.

There are privacy concerns, however, and the Justice

Department is still studying which types of data it can legally

use, Schroeder said.

"That kind of system works effectively only if all of the

potentially disqualifying information that has been gathered by

any federal, state or local authority is accessible to the

database, and that's not the case today," he said.

It is not clear what changes to the background checks would

have prevented the mass shooting in Newtown, because the killer

appeared to have used weapons his mother bought legally.

Other proposals for executive action by Obama include

sharing information with state and local law enforcement about

possibly illegal purchases; maintaining data on gun sales for

longer periods to help with investigations; and restricting the

importation of certain military-style weapons, as President

George H.W. Bush did in 1989.

A pro-gun control mayors' group co-chaired by New York City

Mayor Michael Bloomberg has pushed the Obama administration

since 2009 to adopt 40 recommendations it said were allowed

under existing law.

One of the 40 has been put into effect, said Mark Glaze,

director of Mayors Against Illegal Guns, and even that

recommendation - requiring gun dealers to report sales of

multiple semiautomatic weapons - drew heated resistance.

In 2011, when the U.S. Bureau of Alcohol, Tobacco, Firearms

and Explosives (ATF) adopted a version of the recommendation

aimed at dealers in states near the U.S.-Mexico border, gun

makers sued and congressional Republicans tried to eliminate

funding for the rule.

A judge upheld it, allowing it to go into effect. The case

is now on appeal.

LOBBYING BLITZ

Bloomberg's group is still pushing the other recommendations

as it makes plans for a lobbying blitz over new laws, such as a

ban on high-capacity magazines. "While they are important,

they're not the big-ticket items. And we're in a big-ticket

world," Glaze said.

The administration also has leeway to act in how it defines

certain categories of people prohibited from buying a gun.

Federal law bars anyone "who has been adjudicated as a

mental defective," but it does not specify whether that means

only a court can disqualify someone, said Michael Volkov, a

former Republican Justice Department official now at the law

firm LeClairRyan.

Another option could be changing how long a firearms dealer

must keep records of a sale - a period that is now three days

but could be extended, Volkov said.

Since the Justice Department began reviewing ideas to

prevent mass shootings in early 2011, it has implemented a

handful of changes.

In May, the department unveiled an automated system to feed

records of federal indictments into the background checks

database, replacing a system in which prosecutors uploaded

information manually.

Schroeder said the department's review of firearms-related

ideas is ongoing. He described the process as informal, and not

one that has produced a formal report.

(Editing by Howard Goller and Paul Simao)