The American Journal of Public Health released a new study recently claiming that a 1995 law tightening access to gun permits in Connecticut led to a 40 percent reduction in gun homicides over the next decade.
While the study has many gun control advocates claiming victory, Reason reported that the study is extremely flawed.
The study works on the premise that “past performance guarantees future results.” But it does not say why those figures were so high or why those trends would continue.
A key element the authors used was comparing Rhode Island’s gun homicide levels to Connecticut’s, which mirrored each other very closely before 1995.
“Claim that Connecticut’s law reduced gun homicides is not based on any fall in Connecticut’s rate (which merely mirrors the national trend) but on an increase in gun homicide rate in Rhode Island (to be precise, 0.724*Rhode Island + 0.147*Maryland + 0.087*Nevada + 0.036*California + 0.005* New Hampshire). Given that Rhode Island is the outlier, it makes more sense to look for things in Rhode Island that increased gun homicide rates in 1998 than to ascribe the entire effect to a change in Connecticut in 1995,” said Aaron Brown, chief risk manager at AQR Capital Management, in an interview with Reason.
Brown claims that Rhode Island’s numbers were an outlier from the rest of the nation.
“Claim that Connecticut’s law reduced gun homicides is not based on any fall in Connecticut’s rate (which merely mirrors the national trend) but on an increase in gun homicide rate in Rhode Island (to be precise, 0.724*Rhode Island + 0.147*Maryland + 0.087*Nevada + 0.036*California + 0.005* New Hampshire),” continued Brown. “Given that Rhode Island is the outlier, it makes more sense to look for things in Rhode Island that increased gun homicide rates in 1998 than to ascribe the entire effect to a change in Connecticut in 1995.”
Law enforcement may have also played a significant role in dropping Connecticut’s real homicide rate, a factor unconsidered in the study.
“Near as I can tell, then, the entire edifice of their result is based on the fact that in Rhode Island over the course of eight years, 52 people made the decision to murder, and the study presumes that because of past patterns, a proportional number of people in Connecticut would also, for some reason, have made the decision to murder over those years minus the laws,” wrote Brian Doherty of Reason.
Another problem with the study is that the authors credit the “permit-to-purchase laws” with reducing handguns falling in the hands of criminals. The study doesn’t take enforcement into consideration.
“Virtually no studies of gun control law take enforcement into account because data are lacking and we don’t really know the degree to which deterrence (people not wanting to violate the law) is a function of levels of enforcement,” wrote the study’s author Daniel Webster in an email to Reason.
There is also an issue with the studies source, primarily the Center for Disease Control and Prevention, where the study collected its data on gun mortalities. The CDC changed their coding of mortality data in 1999, making the number of deaths and death rates incomparable to that of previous years.
The study evaluated death and death rates from 1995 to 2005.
These issues cast serious doubt in the study’s conclusion that tougher background checks reduce gun homicides.