In the aftermath of the mass shooting at a high school in Florida, politicians and pundits quickly offered facts and figures about guns in the United States.
NRA spokeswoman Dana Loesch said that in one year, mass public shootings caused more deaths and injuries in France than in the United States throughout the entire Obama administration. (That’s Mostly False.) Bernie Sanders said that "40 percent of the guns in this country are sold without any background checks." (That’s False.)
In North Carolina, Democratic state Rep. Pricey Harrison of Greensboro recently tweeted statistics that emphasize America’s obsession with guns.
"The US has approximately 5% of the world's population and 42% of civilian gun ownership," Harrison tweeted on Feb. 15. She has about 4,000 Twitter followers.
She continued: "We must change the gun culture to gun violence prevention. NC Dems have filed comprehensive gun safety bills repeatedly since the Sandy Hook tragedy w/zero movement."
She’s roughly correct about the United States accounting for 5 percent of the world’s population, according to the U.S. Census Bureau. Experts agree that Americans have more guns than citizens of any other country in the world.
But, globally speaking, is Harrison right about the United States’ share of gun ownership?
"... in 2007, the number of civilian-owned firearms in the US was 88.8 guns per 100 people, meaning there was almost one privately owned gun per American and more than one per American adult. The world’s second-ranked country was Yemen, a quasi-failed state torn by civil war, where there were 54.8 guns per 100 people," the writer, German Lopez, explained.
"Another way of looking at that: Americans make up less than 5 percent of the world’s population yet own roughly 42 percent of all the world’s privately held firearms," Lopez wrote.
The Switzerland-based group actually offered a less specific estimate. On page 46 of the survey itself, the group estimated that the United States is home to "roughly 35-50 percent" of the world’s civilian-owned guns.
Lopez, for his part, told PolitiFact that he split the difference in the range.
"It's pretty typical in research to just take the average of a range," he said. "So the range here is 35-50. If you take the average of this, it lands at about 42. That's with a margin of error of about 7.5, obviously, but it's just a shorthand for what the research finds."
The Small Arms Study from 2007 remains the most comprehensive research private gun ownership worldwide, said Adam Lankford, a professor at the University of Alabama and author of the widely-cited study "Public Mass Shooters and Firearms: A Cross-National Study of 171 Countries," published in 2016.
The Small Arms Study is an independent research project located at the Graduate Institute of International Studies in Geneva that’s supported by the Swiss Federal Department of Foreign Affairs, as well as donations from other governments. The project compiles data using a "worldwide network" of researchers.
Lankford agreed with Lopez’s methodology. If you take the survey’s average total of civilian firearms in the U.S. (270 million) and compare that with the survey’s average total globally (645 million), you get 41.8 percent.
Guns are hard to track
A 2009 National Institute of Justice report found the number of civilian-owned guns in the United States to be about 310 million, but didn't provide comparable global data.
Pew Research Center, one of the world’s leading nonpartisan research firms, recently published a study on guns in America that found 42 percent of Americans live in a household with a gun. But the center hasn’t collected data from other countries, "so we can’t compare our US gun data to the rest of the world," spokeswoman Haley Nolan said.
Governments don’t track firearms across the board. And many surveys rely on people to self-report guns.
"We only have a rough guess of what there is in the U.S. We have no idea how many guns are in South America," said Philip J. Cook, professor of public policy studies at Duke University and co-author of the book "Gun Violence: The Real Costs." South America has a lot of guns that were bought underground, he said.
In the ballpark?
David Hemenway, professor of health policy at Harvard University and author of the book "Private Guns, Public Health," agreed that global estimates are squishy.
"It’s very, very hard," Hemenway said. The best way to estimate the number of firearms in each country would be to have every country track guns that are bought and sold, he said. "Even then, you only get the legal guns."
That said, he thinks Harrison’s claim is generally accurate compared to other estimates.
"That sort of number is thrown around all the time," Hemenway said. "It’s pretty high validity. This seems to be in the ballpark of the figures I’ve seen."
Harrison said that the United States has approximately 5 percent of the world's population and 42 percent of civilian gun ownership. Those numbers are based on a study that’s now 10 years old. And experts say tracking guns is very difficult. But Harrison’s claim is on roughly par with the information available. We rate this claim Mostly True.