I can see it now.  The NRA annual meeting is about to kick off in Indianapolis and I’ll bet you dollars to doughnuts that every speaker at the banquet and other public events will be told to say something nasty about Mike Bloomberg’s new campaign to “get rid” of guns.  What’s going on is that Bloomberg has announced that he’s going to spend 50 million bucks to bankroll a new organization, Everytown for Gun Safety, to build a grass-roots movement across the country that will mobilize voters to enact background checks at the state level to counteract the NRA whose power at the federal level has prevented an expansion of national background checks from taking place.

Bloomberg and many other gun-control activists are convinced that the key to cutting down the rate of gun violence is the ability of the government to keep guns out of the hands of disqualified individuals (felons, mentally ill, etc.) by requiring pre-transfer clearance for anyone who wants to acquire a handgun regardless of whether the transfer occurs in a retail store, a gun show, or two people simply standing in the street.  The evidence supporting this argument can be found on the Everytown website, and it goes like this.

According to Bloomberg’s organization, in 2010 there were 14 states plus DC that required background checks for all handgun sales, and together these states had a 3.17 rate (per 100,000) for gun deaths, whereas the remaining 34 states (CO and DE were excluded due to new laws) registered a gun homicide rate of 5.09; a difference between the two groups of 38%.  If Bloomberg’s group is correct in asserting that universal background checks would bring the gun homicide rate in the country as a whole down to 3.17, we would be talking about at least several thousand less gun deaths each year, and that ain’t chopped liver, even if you’re the former Mayor of New York.

But the moment that anyone come up with a plan to curb gun violence, I always try to figure out whether the plan really aligns itself with the data that is used to explain how and why it’s going to work. Or are we looking at what we often encounter in the gun debate, namely, a confusion between coincidence and causality which has a way of somehow obscuring the facts?  I’m afraid that in the case of Bloomberg’s continued love affair with background checks, it may be a little of both. Here’s what I mean.

Of the 14 states that required background checks for all handgun transfers, nine of them had rates of gun homicides lower than the national average going back to 1970 and before.  The fact that many of these states at some point instituted background checks at the state level wasn’t necessarily the cause of lower gun homicide rates because most of these states had lower homicide rates before any gun control laws were put into effect. For that matter, Mike Bloomberg’s own city, New York, had the most severe background check system,, the Sullivan Law, on the books since 1908.  But the city experienced a severe increase in gun homicide between 1988 and 1993, and then saw the greatest drop in gun violence of any major city in the United States over the next twenty years, a trend that started under Rudy Giuliani but increased even more during Bloomberg’s stint in City Hall.

Don’t get me wrong. Study after study has shown that when you pass gun control laws, the number of gun owners goes down, which no doubt leads to less guns, which probably results in less crime.  But Mike Bloomberg’s successful effort to make New York City safe from gun violence was not, according to his own testimony, due to any change in the laws.  It was the result of smart and aggressive policing and his 50 million bucks wouldn’t cover the costs of such a strategy across the river in Hoboken, never mind across the United States.