Sen. Charles Schumer, the chief supporter of legislation to impose universal background checks, calls them the "sweet spot" for curbing gun violence and the likelihood of getting legislation passed.

U.S. law requires that any time someone buys a gun from a federally licensed gun dealer, the dealer is required to run a check on the potential buyer for possible criminal and mental issues. Records are kept by state and federal agencies.

Convicted felons, people convicted of violent domestic crimes and those determined by courts to be dangerously mentally ill are prohibited by federal law from buying firearms.

However, federal law does not require background checks for what are considered private transactions.

And there are gaps in the existing system -- many states don't report the names of people who have been labeled dangerously mentally ill. And there are huge gaps in the database. For instance, the Virginia Tech shooter who killed 33 people in 2007 passed two background checks when buying guns because Virginia didn't submit his mentally ill status to the database.

Would they work: Achieving this goal will take a combination of the executive action the president took on Wednesday and legislation to change existing laws on the requirement of background checks.

Obama said Wednesday that he has taken action to address legal barriers to states sharing relevant information to the database and other measures like ensuring that physicians can ask patients about guns in their homes.

The legislation Schumer is considering would encourage states to comply with sharing relevant information to the database by withholding federal funds for their law enforcement initiatives -- the federal government can't require the states to comply, but it can make it worth their while.

It would also make it a crime for someone to sell a firearm without taking the buyer to a place where a background check can be performed. Enforcement would be an issue though -- it could be difficult to prove whether a firearm already on the market was sold before or after the requirement was implemented.

Across the country, more than a million people failed background checks to buy guns during the past 14 years because of criminal records, drug use or mental health issues, according to FBI figures. That figure, however, is a small fraction of overall gun sales.

Mental illness measures

Four of the 23 executive actions that Obama announced on Wednesday address access to mental health care through Medicare and Obamacare.

Medicare is the largest provider of mental health care in the country and the Affordable Care Act opens access to millions of other Americans covered by the federal government.

Another executive action was to open a national dialogue on mental health led by Health Secretary Kathleen Sibelius and Education Secretary Arne Duncan.

Obama also clarified that a provision in Obamacare does not prohibit doctors from asking their patients about guns in their homes.

A number of mass shootings have been committed by people known to have struggled with mental illness which has renewed calls to address mental illness in a more comprehensive manner.

Federal legislation restricting access to guns for the mentally ill was firs enacted in 1968.

Would it help?: A number of mental health advocacy groups came out in support of the president's announcement.

The National Alliance on Mental Illness released a statement applauding the initiatives put forth from Vice President Joe Biden's task force, calling it the chance to fix the broken health care system, "an opportunity that comes only once in a generation."

The group also supported that the president "correctly noted" that many of the mentally ill were not violent.

NAMI expressed its hope that the attention could help fill gaps in the mental health system.

FBI statistics showed about 1 percent of applicants who failed a background check were turned down for reasons related to mental health.