Guns are the leading cause of death among children. A new study concludes that states that have eliminated gun restrictions have higher death rates among children than states that have retained restrictions. The National Rifle Association, which opposes any restrictions on access to guns, dissented.

The NRA, the Supreme Court, and the gun-loving Republican Party can take credit for the deaths of thousands of children. Their extremist interpretation of the Second Amendment is lethal to children.

The New York Times reported:

Firearm deaths of children and teenagers rose significantly in states that enacted more permissive gun laws after the Supreme Court in 2010 limited local governments’ ability to restrict gun ownership, a new study has found.

In states that maintained stricter laws, firearm deaths were stable after the ruling, the researchers reported, and in some, they even declined.

Guns are the leading cause of death in the United States for people ages 1 through 17, according to the Centers for Disease Control and Prevention. Dr. Jeremy Faust, an emergency room doctor at Massachusetts General Brigham Hospital in Boston, who was the study’s lead author, said he was dismayed to find that most of the children’s deaths were homicides and suicides.

“It’s surprising how few of these are accidents,” Dr. Faust said. “I always thought that a lot of pediatric mortality from guns is that somebody got into the wrong place, and I still think safe storage is important, but it’s mostly homicides and suicides.”

John Commerford, executive director of the NRA Institute for Legislative Action, called the study “political propaganda masquerading as scientific research.”

The study, published Monday in JAMA Pediatrics, examined the 13-year period after the June 2010 Supreme Court ruling that the Second Amendment, which protects the right to bear arms, applies to state and local gun-control laws. The decision effectively limited the ability of state and local governments to regulate firearms.

The researchers classified states into three categories based on their gun laws: most permissive, permissive and strict. They used a Centers for Disease Control and Prevention database to analyze firearm mortality trends from 1999 to 2010 — before the Supreme Court ruling — and compared them with the 13-year period afterward.

Nationally, they found that the number of people under 18 who died from firearm injuries in the period after the ruling exceeded the projected figure for that time by about 7,400, with a total of about 23,000 fatalities.

But in the nine states with the strictest gun laws, youth firearm deaths did not increase. In four — California, Maryland, New York and Rhode Island — they dropped significantly.

The average age of those killed was 14, according to the study, which was coauthored by researchers from Yale New Haven Hospital, the University of California San Francisco School of Medicine and the schools of public health at University of Pittsburgh and Brown University.

Advocates for stricter gun laws praised the study, saying it expanded the evidence that gun safety laws save lives.

“We have shown in the past that states that have the strongest laws when it comes to gun policy have a gun violence rate that’s 2.5 times less than the states with the weakest,” said Nick Suplina, senior vice president for law and policy at Everytown for Gun Safety. “Lawmakers that refuse to take action or further loosen laws are putting kids’ lives at risk.

He also said that gun safety laws had multiple benefits, reducing accidental shootings, while also preventing youth suicides and school shootings. “Three of four school shootings are committed with a weapon taken from the home of the family or a close relative,” Mr. Suplina said.