Because the RAND researchers' criteria for including studies in their final analysis were rigorous, for the majority of policies and outcomes, there was not enough good research to make any definitive statements — a clear indication of how little we know about how to prevent gun violence. But there were notable exceptions.
There is moderate evidence, for instance, that “stand your ground” laws, which remove the requirement for gun owners to attempt to retreat from a situation before using lethal force, increase total rates of homicide. A 2013 study, for instance, found that states passing such laws saw 6 percent to 11 percent increases in their total homicide rate. Another study found that Florida experienced a significant 24 percent increase in total homicides and 32 percent increase in firearm homicides following enactment of the stand-your-ground law in 2005.
The NRA has been a vigorous champion of these laws. After the shooting of unarmed black teenager Trayvon Martin in 2012, the group released a statement saying stand-your-ground “empowers lawful people to defend themselves, and deters would-be murderers, rapists and robbers,” and “the alternative leaves the innocent in danger.”
The NRA also opposes expanding background checks for gun purchases because “background checks don’t stop criminals from getting firearms.” The research compiled by RAND shows moderate evidence that dealer background checks decrease rates of firearm homicide and limited evidence that background checks decrease violent crime and total homicide rates.
All told, the RAND report can be read as an indictment of the gun policy agenda favored by the NRA and its allies in Congress. On balance, the evidence suggests a number of NRA-backed policies, like stand-your-ground laws and permissive concealed carry rules, increase gun violence. Conversely, there is good evidence showing that measures opposed by the NRA, like expanded background checks and child access prevention laws, could reduce the overall toll of gun violence.
Setting individual policies aside, the chief argument of the new RAND report is that there is an urgent need for more, better research into gun violence and how to prevent it. “Many of the possible effects of gun policies that are raised in policy debates have only rarely — or never — been studied rigorously,” RAND's Andrew R. Morral, the project's leader, writes.
The NRA did not respond to a request for comment.