Fun with MAIG numbers

[minus_p]

Here in Vermont I ran across a few claims that our "lax gun laws" are fuelling "gun crime" in neighboring states that don't enjoy the freedom that we do. Following these claims to a 2010 report "Trace the guns" (http://www.mayorsagainstillegalguns....uns_report.pdf) which along with a companion website (http://www.tracetheguns.org/#) provided a few interesting bits of information. Now I know that there are all kinds of problems with making inferences from gun trace data, not to mention the credibility of this particular information source. But I was curious to see how the numbers played out in my own region with respect to the hand wringing about how we are responsible for all the violence in Boston and New York.

There were 43,254 guns recovered in 2009 at crime scenes and traced to another state, or 30% of the total. There were 3,607 of these guns in NY, 689 in MA, and 1,792 in NJ. The contribution of Vermont to these figures was 41 (1%), 35 (5%), and 7 (0.3%) respectively. Not too impressive. Maybe if we added up all of the crime guns exported from VT, NH, ME, and PA the numbers would show that these neighboring states with lax gun laws are fueling crime in our more restrictive neighboring states. All of the crime guns traced to VT, NH, ME, and PA account for 457 (12%) of guns from other states found in NY, 252 (37%) in MA, and 415 (23%) in NJ, and the majority of these were traced to PA. Keep in mind that these represent only 30% of the guns traced, as the rest are sourced within their own state (no breakdowns were provided). MA imports a higher percentage of its crime guns from its neighbors than NY or NJ, but it is still only about a third of the guns traced. Even if we assume that traced imported guns are a higher percentage in those states - say, 40%, the contributions of neighboring states with less restrictive laws to the overall number of recovered guns ranges from 9% in NY to 26% in MA. Clearly the majority of guns are coming from considerable distances, for reasons other than just the restrictiveness of gun laws - from states like VA, NC, SC, GA, and FL.

Another thing I noticed was that quite a few recovered guns are traced to states with very restrictive laws. For example, CA is the 10th highest "exporter of crime guns" with 1,772 (again, recognizing that trace data doesn't really prove this kind of statement). The figures seem to be often obfusticated by reporting on a per capita basis, but if the problem is crime then what matters is the raw numbers. There were 239 guns traced to MA in 2009, about the same number as NH which exported 242. The number traced to NY was 517. There were 242 traced to NJ, again about the same number as NH. Together, NY, NJ, and MA exported 998 traced guns used in crimes, which far surpasses the 607 exported by the three least restrictive states in the northeast. Now, if we look at PA it is a different story. There were a whopping 1,777 guns traced to PA from other states, about the same number as for CA. Interestingly, the gun laws in PA would appear to be more to the likes of MAIG, with entries like "Requires background checks for all handguns sold at gunshows", "Allows criminal penalties for buying a gun with false information", "Allows criminal penalties for selling a gun without a poper background check", and so forth. And of course PA has Philadelphia.

To summarize: Even including the lopsided contribution of PA, guns traced to neighboring states with less restrictive laws comprise only a small proportion of guns recovered at crime scenes in NY, NJ, and MA. The contribution of Vermont specifically to "gun crime" in these states is miniscule. The percent is bigger in MA, but the overall number of guns recovered there is comparatively small. Many traced guns originate in the northeastern states with the most restrictive laws. As many guns are traced to MA and NJ as are traced to NH and ME. Almost twice as many are traced to NY. The state in the northeast with the highest number of guns traced from other states (PA) has no "gunshow loophole" and already has state laws in place to criminalize improper purchasing and selling. Guns recovered in NY are more likely to have come from southeastern states at greater distance than neighboring states with less restrictive laws, suggesting that these laws may not be making much of a difference to the flow of "illegal guns" from other states.

Now there are limits on how far you can take numbers like this, even if you uncritically accept their validity. The purpose for me was simply to demonstrate that Bloomberg and Menino have no business complaining about their northern neighbors, using their own numbers. Other comparisons may not hold up as well. Please verify for yourself before using these figures for any consequential purpose.