The country’s largest doctor group just took its most aggressive stance on gun control yet

The American Medical Association (AMA), the US’s largest physician group, officially endorsed a variety of gun control measures on Tuesday.

According to Lindsey Tanner at the Associated Press, the AMA, which represents nearly a quarter of the US’s physicians, backed several new gun laws at its annual policy meeting. Here are some examples, from the AP:

Support for the policy platform was overwhelming — with a vote of 446 to 99 that included backing from some doctors who own guns, according to the AP.

In the past, the AMA has backed other gun control approaches. As the AP reported, “it has supported past efforts to ban assault weapons; declared gun violence a public health crisis; backed background checks, waiting periods and better funding for mental health services; and pressed for more research on gun violence prevention.”

But the latest vote signals a more aggressive approach by the AMA as gun violence gets more attention due to high-profile mass shootings, such as the Marjory Stoneman Douglas High School shooting in Parkland, Florida, in February.

There’s good reason for that extra attention: The US still far outpaces its developed peers when it comes to gun violence. And the research suggests that the nation’s lax gun laws are a major reason for the higher rates of gun deaths.

The US has nearly six times the gun homicide rate of Canada, more than seven times that of Sweden, and nearly 16 times that of Germany, according to United Nations data compiled by the Guardian. (These gun deaths are a big reason America has a much higher overall homicide rate, which includes non-gun deaths, than other developed nations.)

Mass shootings actually make up a small fraction of America’s gun deaths, constituting less than 2 percent of such deaths in 2016. But America does see a lot of these horrific events: According to CNN, “The US makes up less than 5% of the world’s population, but holds 31% of global mass shooters.”

So why is the US such an outlier? Researchers widely believe it’s due to America’s tremendous abundance of and access to guns. According to estimates, 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 research, compiled by the Harvard School of Public Health’s Injury Control Research Center, is clear: After controlling for variables such as socioeconomic factors and other crime, places with more guns have more gun deaths. Researchers have found this to be true not just with homicides but also with suicides (which in recent years accounted for around 60 percent of US gun deaths), domestic violence, and even violence against police.

As a breakthrough analysis by UC Berkeley’s Franklin Zimring and Gordon Hawkins in the 1990s found, it’s not even that the US has more crime than other developed countries. This chart, based on data from Jeffrey Swanson at Duke University, shows that the US is not an outlier when it comes to overall crime:

Instead, the US appears to have more lethal violence — and that’s driven in large part by the prevalence of guns.

”A series of specific comparisons of the death rates from property crime and assault in New York City and London show how enormous differences in death risk can be explained even while general patterns are similar,” Zimring and Hawkins wrote. “A preference for crimes of personal force and the willingness and ability to use guns in robbery make similar levels of property crime 54 times as deadly in New York City as in London.”

This is in many ways intuitive: People of every country get into arguments and fights with friends, family, and peers. But in the US, it’s much more likely that someone will get angry at an argument and be able to pull out a gun and kill someone.

Stronger gun laws could help combat this. A 2016 review of 130 studies in 10 countries, published in Epidemiologic Reviews, found that new legal restrictions on owning and purchasing guns tended to be followed by a drop in gun violence — a strong indicator that restricting access to guns can save lives. A review of the US evidence by RAND also linked some gun control measures, including background checks, to reduced injuries and deaths.

But the US maintains some of the weakest gun laws in the developed world. Until America confronts that issue, it will continue seeing more shootings than the rest of the developed world.

For more on America’s gun problem, read Vox’s explainer.