The Washington Post Fact Checker will surely earn the enmity of liberals after backing up Sen. Marco Rubio’s recent claim that gun laws wouldn’t have prevented the recent mass shootings and earning a rare Gepetto.
“None of the major shootings that have occurred in this country over the last few months or years that have outraged us, would gun laws have prevented them.”
— Sen. Marco Rubio (R-Fla.). interview on CBS’s “This Morning,” Dec. 4, 2015
First of all, we should note that there is an unbridgeable gap in opinion about efficacy of various gun proposals, particularly regarding assault weapons and high-capacity magazines.
“The common thread that binds most mass shootings is semiautomatic firearms with the ability to accept a high-capacity detachable ammunition magazine ,” said Avery Palmer, communications director at the Violence Policy Center, which supports restrictions on guns. “These can range from assault rifles, pistols, and shotguns, to compact, high-capacity pistols marketed for concealed carry. Today’s gun industry has embraced increased lethality as its marketing lodestar, and one key element in reducing the occurrence and severity of mass shootings lies in ratcheting down the firepower in civilian hands.”
By contrast, gun-rights supporters argue that bans on certain weapons and large-capacity magazines would accomplish little. There are already more than 5 million AR-type rifles  in circulation in the United States, ownership of which would have been grandfathered under proposed bans.
A previous nationwide assault-weapons ban, which lasted 10 years and lapsed in 2004, was easily circumvented by gun manufacturers, in part because of various loopholes. The evidence is mixed on how effective that ban was, with both sides often cherry-picking from the most comprehensive report  on that law, written in 2004 by Christopher Koper of George Mason University. “The ban did not appear to affect gun crime during the time it was in effect, but some evidence suggests it may have modestly reduced gunshot victimizations had it remained in place for a longer period,” Koper wrote in 2013 .John R. Lott Jr., at the pro-gun Crime Prevention Research Center, notes that such bans would target .223-caliber weapons but would not affect more powerful semiautomatic rifles using .30-06 caliber, which are used for hunting deer.
The Pinocchio Test
This is certainly a depressing chronicle of death and tragedy. But Rubio’s statement stands up to scrutiny — at least for the recent past, as he framed it. Notably, three of the mass shootings took place in California, which already has strong gun laws including a ban on certain weapons and high-capacity magazines.
Gun-control advocates often point to the experience in other countries that have enacted gun laws that heavily restrict gun ownership; as we have shown , quantitative measures of cross-comparative crime statistics, especially where the crime is not consistently defined (i.e., “mass shooting”), usually end up being apples-to-oranges comparisons. It is possible that some gun-control proposals, such as a ban on large-capacity magazines, would reduce the number of dead in a future shooting, though the evidence for that is heavily disputed. But Rubio was speaking in the past, about specific incidents. He earns a rare Geppetto Checkmark.
The Geppetto Checkmark