(CNN) — The rate of gun-related murders fell sharply in the 10 years after Connecticut implemented a law requiring people buying firearms to have a license, according to a study.
In 1995, a permit-to-purchase handgun law went into effect in Connecticut, stating that people who want to buy a gun must apply for a license (or permit) with the local police, a process that involves a background check, as well as complete at least eight hours of gun safety training. The law also raised the minimum purchasing age from 18 to 21.
To assess the effect of this law, researchers identified states that had levels of gun-related homicide similar to Connecticut before 1995. These include Rhode Island, New Hampshire and Maryland. When the researchers compared these states to Connecticut between 1995 and 2005, they found the level of gun-related homicide in Connecticut dropped below that of comparable states.
Based on the rates in these comparable states, the researchers estimated Connecticut would have had 740 gun murders if the law had not been enacted. Instead, the state had 444, representing a 40% decrease.
“I did expect a reduction [but] 40% is probably a little higher than I would have guessed,” said Daniel Webster, director of the Johns Hopkins Center for Gun Policy and Research who led the study, which was published Friday in the American Journal of Public Health.
“I think we have strong evidence that this is a policy that saves lives, and not a small number of lives,” Webster said.
Ten states have laws similar to Connecticut’s, including background check requirements. It is hard to know what effect permit-to-purchase laws have without looking in these other states, said John R Lott Jr., president of the Crime Prevention Research Center, a gun rights advocate and columnist for Fox News. “If 10 states passed a law, eight could increase and two could fall, and how do I know that it was because of the gun law?” he said.
Although Webster said he would like to study the effect of gun laws in other states, that research is not practical. Most states passed meaningful gun laws, such as laws requiring background checks, long ago, “frankly before I was born,” and it would be hard to know how those laws were enforced back then, and how society responded to them, he explained. In addition, information from death certificates was less readily available from the Centers for Disease Control and Prevention before 1980, he said.
Massachusetts passed a gun law more recently, in 1998, and the number of firearm-related homicides reportedly increased after the law. However, this law did not really change how people buy guns in the state because a law requiring background checks had already been in place for decades, Webster said.
The 40% decrease in firearm-related homicide that Webster’s study suggested for Connecticut is “pretty substantial and quite impressive,” said Brad J. Bushman, professor of communications and psychology at The Ohio State University who studies gun violence in the media and aggressive behavior. Bushman was not involved in the current study, nor has he conducted any research with Webster, although the two serve together on President Obama’s committee on gun violence and the National Science Foundation youth violence advisory committee.
Webster and his colleagues took into account other factors that could have contributed to the decline in gun-related homicide, such as changes in population size and shifts in demographics, when they compared the numbers in Connecticut to those in similar states before and after 1995. The fact that they still predicted the drop in firearm homicide in Connecticut at the turn of the 21st century suggests it can’t be because of these other factors, Bushman said.
The researchers also looked at rates of nonfirearm homicide and found no difference between Connecticut and other states across the time frame of the study (1985-2005), suggesting the drop in gun-related murders in Connecticut was not simply due to waning murder rates in the state overall.
Webster and his colleagues did not look at rates of gun-related violence in the study because inconsistencies in police reports of violence would make interpretation of the numbers difficult, Webster said.
It is hard to predict whether Connecticut would continue to see lower rates of gun-related homicide beyond 2005, Webster said. He and his colleagues found the numbers did rebound after the period in the study. Although it is not clear why rates of gun death rose in Connecticut starting in 2006, there was also an increase in gun deaths nationwide in that time, Webster said.
In an earlier study, Webster and his colleagues found there was an inverse, although smaller, change in Missouri after the state repealed its 1921 permit-to-purchase law in 2007. They saw a 23% increase in gun-related murders between 2007 and 2010, compared to between 1999 and 2007.
Webster presented the findings of the Connecticut and Missouri studies on June 11 at a press event in Washington held by Faiths United To Prevent Gun Violence, a coalition of faith leaders from across the United States, to support laws like the one in Connecticut. “I’m glad that they are mobilizing to try to enact a policy that will save lives,” Webster said.
The U.S. Congress will also introduce a bill that would allow the federal government to give money to states with handgun purchaser licensing laws to help support systems in those states for reviewing applications and issuing permits.
“A lot of the debate around guns has more to do with the culture, do you like or hate guns, and how do you interpret the Second Amendment,” Webster said. “What’s important here is that a bill is introduced that is based on a foundation of scientific research showing this will save lives.”
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