If the rejected purchaser is a convicted felon, under a restraining order, the subject of a domestic violence misdemeanor conviction or meeting similar criteria, authorities are more apt to follow up after denying the sale.
Here's how the winnowing-down worked in 2010:
The FBI referred 76,142 background check denials to a branch of the Bureau of Alcohol, Tobacco, Firearms and Explosives for screening. There, the vast majority of the denials were judged to fall short of the guidelines for further action, or were overturned.
The rest, 4,732 denials, were referred to ATF field divisions for investigation. Most went no farther. In the majority of those cases, authorities saw insufficient merit for prosecution or concluded the federal or state guidelines for proceeding were not met. And in 480 cases, the people investigated were found not to have merited the denial.
Ultimately, the field divisions referred 62 charges for consideration by prosecutors, and they went ahead with 44, winning 13 guilty pleas and dismissing 10 in plea agreements. The rest were continuing past the period covered in the report.
Prosecutions are only one way to measure the performance of background checks. The same system that ultimately produced few convictions also blocked tens of thousands of gun sales to people prohibited from buying them, forcing them to get their weapons another way or go without. Most federal gun prosecution takes place outside the background check system.
Even so, the government is sensitive to criticism that enforcement overall is lagging. President Barack Obama's recent executive actions on gun control include steps to spur prosecution, in what can be seen as a tacit acknowledgment that existing laws have not been used to full effect.
BIDEN: "Let me give you an example: 98 percent, according to a New York Times poll, 98 percent of the American people believe that there should be tighter controls on who can own a gun."
THE FACTS: It would be a miracle if 98 percent of Americans agreed on anything. And by any measure, that many don't agree on guns.
In a New York Times/CBS News poll, 54 percent said "gun control laws should be made more strict," 34 percent said they should be left as they are and 9 percent said they should be less strict. The poll also found that 92 percent would favor "a federal law requiring background checks on all potential gun buyers," a result on par with the level of support that proposal gets in other polls. Biden made the comment last week at a Google Plus forum.
How elusive is 98 percent agreement?
Americans came close after the terrorist attacks of Sept. 11, 2001. In October 2001, Gallup found that 9/11 mastermind Osama bin Laden had an unfavorable rating of 97 percent.
Associated Press writers Jennifer Agiesta and Alicia A. Caldwell contributed to this report.
EDITOR'S NOTE _ An occasional look at claims by public figures that take shortcuts with the facts or don't tell the full story
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