MONDAY, March 2, 2020 (HealthDay News) -- Gun deaths in kids younger than 15 are 13% lower in U.S. states with gun-storage laws than in states without these regulations, a new study finds.

Researchers from Boston Children's Hospital conducted a 26-year analysis of states with and without child access prevention (CAP) laws. CAP laws are in place in half of U.S. states. They're designed to protect children from accessing firearms by holding the guardian legally responsible for the child's access.

"Looking at all these laws, the negligence laws seem to have the best effect," said senior investigator Dr. Eric Fleegler, a pediatric emergency physician at Boston Children's Hospital.

"And as the negligence laws get more stringent in terms of holding a gun owner legally responsible for a child actually accessing a gun, or even potentially accessing a gun, the death rates in children decrease," he said in a hospital news release.

The authors reviewed nearly 14,000 deaths from firearms in U.S. children up to 14 years old from 1991 to 2017. Researchers categorized CAP laws in each state by overall restrictiveness, and paired that with this information.

An estimated 4,000 child deaths could have been prevented if all 50 states had the strongest type of negligence laws during the study period, the researchers said.

"The message is clear," Fleegler said. "Had all of the states had some types of negligence law we would have expected thousands of children not to have died."

CAP laws can range from recklessness laws to negligence laws, each with a different level of restrictiveness:

• Recklessness laws criminalize providing firearms to children.
• The "Child Uses" laws hold the parent responsible if a child accesses and uses an improperly stored firearm. These are the least restrictive negligence laws.
• The more restrictive "Child Accesses" laws apply where a child accesses an improperly stored firearm but does not use it.
• The most stringent negligence laws, "Child Could Access" laws, apply if a child could potentially access an improperly stored firearm.

The "Child Could Access" laws are associated with a 29% reduction in all-intent firearm deaths and a 59% reduction in unintentional firearm deaths, according to the study.

"The reduction in firearm fatalities is greater in those states with stronger negligence laws compared with states with weaker laws," said co-author Hooman Azad, a second-year medical student at Northwestern University in Chicago. "While it does not absolutely mean causation, there are very strong associations between the type of CAP law and the number of firearm fatalities in children."

The guiding principle of CAP laws is safe firearm storage. Proper gun storage includes securing a firearm in a locked container with the ammunition locked in another container.

"We know proper storage happens in a very small percentage of households with a firearm," said Fleegler, "but this analysis shows that the passage of negligence CAP laws has the potential to reduce firearm fatalities in children."

The study was published online March 2 in JAMA Pediatrics.

More information

C.S. Mott Children's Hospital has more on gun safety and kids.