Stronger gun laws tied to decreased firearm homicides

Researchers at Boston Children's Hospital reviewed all available articles published in peer-reviewed journals from January 1970 to August 2016 that focused specifically on the connection between firearm homicide and firearm laws. Of the 582 abstracts found, only 34 met the criteria for inclusion. These 34 studies were weighted for quality and divided into five general categories: those that strengthened background checks, those that curbed firearm trafficking, those that improved child safety, those banning military-style assault weapons and those restricting firearms in public places.

"Overall, we found evidence that stronger firearm laws are associated with decreased homicides due to firearms," says lead author Lois Lee, MD, MPH, of Boston Children's Hospital's Division of Emergency Medicine and Harvard Medical School. "Specifically, the laws that seemed to have the most effect were those that strengthened background checks and those that required a permit to purchase a firearm."

Laws that banned assault weapons, improved child safety or aimed to limit firearm trafficking had no clear effect on firearm homicide rates. Laws that aimed to restrict guns in public places had mixed results, with some studies showing such laws reduce homicides and others not finding this result. However, the researchers point to the need for larger, longer-term studies to draw conclusive results.

"One of our most important findings is the lack of high-quality research on this topic, especially in relation to the major health impact gun violence has had in this country," says co- author Eric Fleegler, MD, MPH, also of Boston Children's Division of Emergency Medicine and Harvard Medical School. "Much of the research really didn't have access to or use the highest quality data or analysis. The quality, number and time frame of these studies is very limited; many didn't study the laws over a long enough time to see the full effects of these types of laws."

Despite these limitations, the findings are consistent with a study the team conducted in 2013, which found that states with stronger firearm legislation had decreased deaths, from both homicides and suicides, compared to states with weaker firearm laws.

"Gun legislation is a very important and controversial issue right now, but our findings show that some laws, specifically those to strengthen background checks and require a permit to purchase a firearm, will not deny people the right to bear arms, but will help protect the public," says Lee. "We hope our findings will help states draft legislation that is useful and sensible to both sides of the gun issue."

The researchers also call for more federal support for gun-related research.

"When you look at other areas of injury prevention, such as motor vehicle safety, there are streams of data," says Fleegler. "There is no funding in health care for serious researchers who are trying to look at firearm data."