OCTOBER 4, 2015
There have been a lot of claims thrown around after the murders at the Umpqua Community College in Oregon. President Obama and the anti-rights groups have been quick to call for more firearms prohibitions, more gun control laws. I wondered if "gun control" works. I looked at the data, and I'd say "gun control" fails.
I put the term "gun control" in quotes for a reason. There are some 23 thousand gun control laws. I doubt that each and every gun control law is equally effective at reducing crime. I don't know how to weight the importance of each law. I also don't know how to compare similar laws between states. For example, is hunter education a part of "gun control", and is it as effective as "mandatory waiting periods" in reducing violent crime? I appealed to the experts to answer that question.
The Brady Campaign to Prevent Gun Violence issues a scorecard each year. They rate the gun prohibitions in each state. I used their system to put the states in order from strict gun laws to lax gun laws. The data is from their state scorecards for the end of 2013. I used FBI crime data from 2012 since it takes time for new laws to change the crime rate. It seemed unfair to judge the effectiveness of a law that had been put in place that same year.
What should we expect to see from the data? If gun control worked, we would see a decrease in criminal violence in the states where criminals gave up their guns due to strict gun control laws, and an increase in crime where gun control laws were lax. If gun control really made a difference, then we could predict the crime rate based on the gun control laws. The graph should look something like this.
What would the data look like if gun control was ineffective? If criminals didn't care about gun laws and the states were otherwise very similar, then we would see very similar rates of violence in each state. That says gun control is not a real factor that determines the crime rate. Knowing how a state ranks in gun laws would not predict their crime rate at all. A statistician would say crime is not correlated with gun control.
Now let's look at the real data. We don't see results like my two examples. Instead, the rate of violent crime varies by a factor of about 6-to-1 between the different states. That means there are factors that influence the rate of crime. I put the states in order of their Brady rank and then plotted the rate of violent crime. In contrast to their claims, the Brady Campaign's rank of gun control laws in each state has almost nothing to do with the rate of violent crime. You can't predict a states crime rate if you know their gun control laws. For example, the states with the lowest and highest crime rates had similar scores by the Brady Campaign.
Maybe the effects of gun control are hidden. Maybe gun control works to control some violent crimes, but not others. I also looked at the rates of aggravated assault and forcible rape to see if they were effected by state gun laws. I put the states in order again and plotted their crime rates. The strictness of a state's gun laws does not predict the rate of forcible rape or aggravated assault. Neither of those violent crimes shows a strong correlation with their ranking by the Brady Campaign.
What do these results tell us? The data tells us that the gun control laws as weighed by the Brady Campaign to Prevent Gun Violence do not control crime. Other laws and public practices might control crime. We see large differences from state to state. Whatever controls crime, it is not those gun laws.
We have seen laws and social trends change with time. Gun ownership has increased by over 60% since the mid 1990s. We would expect crime to rise if guns caused crime. In fact we see the opposite effect. According to FBI data, the rate of violent crime has fallen almost 50 percent over the same time period.
I've had anti-gun spokesmen tell me that gun control stopped crime and saved lives. Now that I've seen the data, I'd say gun control has very little effect on criminal violence. I'd say the anti-gun spokesman lied to me.
So did President Obama.