There’s a study getting some traction out of the Bloomberg funded Johns Hopkins Center for Gun Policy and Research that claims Connecticut’s handgun law is saving lives. In fact, it’s the same study Congressional Democrats are using as justification for their proposal to license all handgun buyers. The problem with making claims about the efficacy of different laws: there isn’t a good way to massage the data to make that determination. There are a huge number of variables that go into the crime rate, and usually the applicable laws don’t have an appreciable impact. However, as an article in Newsweek proclaims, this time they have proof! Here’s the claim . . .
A decades-old gun law in Connecticut requiring residents to have a permit before purchasing a handgun is credited with helping to reduce the state’s firearms-related homicide rate by 40 percent, according to a new study.
The “decades old gun law” in question is the firearms owner licensing requirement in Connecticut. Anyone who wants to buy a handgun must have a permit prior to purchase. The sales are tracked. This of course only applies to law abiding gun owners, as criminals are legally exempted from registering their firearms. How exactly did they come up with this claim of staggering effectiveness?
They compared Connecticut’s homicide rates in the decade before the adoption of the law, to the expected numbers 10 years after its implementation, had it not passed. For data within the decade after the law was approved, researchers analyzed three states with homicide rates that closely mirrored the numbers in Connecticut—California, Maryland and Rhode Island, Webster tells Newsweek. Those three states and Connecticut also had other similar types of gun policies.
First, the overall firearm homicide rate has been declining across the country over the last four decades. In fact, the overall decline in the murder rate corresponds very neatly with the time period that the study studied. So if they were comparing the homicide rate prior to the implementation of the law with the homicide rate in the years thereafter, there’s already a strong trend downwards even without the new laws. Keep in mind that the overall rate includes states that didn’t adopt such draconian laws, like Texas and Pennsylvania.
Second, predicting the homicide rate given a “what-if” scenario such as the non-passage of that same law is about as accurate a science for making solid assessments as phrenology is for detecting psychological illness. When you’re looking at something as complex as the homicide rate, there are a ton of factors at play that can influence that number that frankly we still don’t understand at all. So when someone posts a study claiming that they have isolated all the variables and make concrete claims, my BS meter starts to ping. Loudly.
The Johns Hopkins study claims that, definitively, the gun control law reduced the number of murders by a significant number. Given the source and the lack of hard statistics, I’m doubtful. I think there’s something that they aren’t seeing driving that number, especially since New York has an identical law and their murder rate has dramatically increased.
Correlation does not equal causation. And correlation based on bogus data is about as useful as runway behind you, altitude above you, and air in your fuel tanks.