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Field Notes from the Digital Prairie

Wednesday, September 4, 2013

Concealed Carry v. Crime, Part II

Some months ago, I posted a design project that charted changes in violent crime rates versus changes in concealed carry laws. It was pointed out to me that, since many of the categories of violent crime included in the FBI's Uniform Crime Reporting tool include attempted crimes (see the UCR's definitions), it was possible that the negative outcomes in violent crime rates that I noted could have been the result simply of an increase in reported attempted crimes resulting from, for example, victims shooting their assailants.

While this seemed unlikely to me, and while I don't have time to build additional infographics representing new data, it was worth looking into. The best way to do so, as far as I could tell, was by examining the murder rate, which does not include attempted murders; therefore, the crimes included would be successfully completed crimes that would almost certainly not have otherwise gone unreported. If the negative outcomes in overall violent crime rates were masking what were in fact positive outcomes by way of an increase in the reporting of attempted crimes, then we should see more positive outcomes in states' murder rates.

Digging into the data (I've updated the spreadsheet where I tracked all of this) we do in fact see a slightly higher number of positive outcomes: seven states had positive changes in 5-year average murder rates compared to the change in the national average, as opposed to four positive changes in overall violent crime rates. However, as with the overall violent crime rate, far more states had negative outcomes.

Positive
  • National average increased, state average decreased: 2 (FL, OR)
  • National average decreased, state average decreased more: 4 (AK[2], CO, MN, TX)
  • National average increased, state average increased less: 1 (ID)
Negative
  • National average decreased, state average increased: 5 (AK[1], AZ, GA, MO, OH)
  • National average increased, state average increased more: 3 (MS, PA, WV)
  • National average decreased, state average decreased less: 13 (AR, KY, LA, MI, MT, NM, NV, NC, OK, SC, TN, UT, VA)

Overall, states that switched from no-issue to shall-issue laws had an average change 15.58 percentage points worse than the national average (compared to an average of 10.13 percentage points worse in overall violent crime rates), while those going from may-issue to shall-issue fared an average of 8.86 percentage points worse (compared to an average of 7.68 percentage points worse in overall violent crime rates). So, if the national murder rate was going up over a given time period, the average state that transitioned to more permissive concealed carry laws saw its murder rate grow faster than the national rate; if the national rate was going down, transitioning states saw their murder rate fall more slowly than the national average. Again, this suggests that more permissive concealed carry laws not only do not prevent murders, they may in fact exacerbate them.

Finally, as before, I looked at how no-issue states' rates compared to the national average, and in all but two years (1982 and 1999) between 1981 and 2010, the murder rate in no-issue states was equal to or less than the national rate, indicating that the inability for citizens to legally carry concealed weapons does not necessarily encourage more murders.

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