A. Writer

Does Gun Control Work?

It’s a well-known that gun ownership rates (the percentage of adults living in a home with at least one gun) have a high correlation to gun deaths. The more guns there are, the more people are being shot and killed. And stricter gun laws correlate to fewer guns. These are statistical facts.

But gun deaths aren’t the problem. Early death is the problem.

In this discussion, murder (including non-negligent manslaughter), suicide, and accidental deaths are the problem. Let’s look at the details of each and how they correlate gun laws.

Evaluating Gun Laws

Comparing gun laws to each other is a tricky business. Small variations in how laws are written can change the meaning dramatically. And there are a variety of different types of gun laws that are difficult to compare effectively.

The Giffords Law Center (who uses the tag line “To Prevent Gun Violence” on their logo) attempts to do just that with their Annual Gun Law Scorecard (i.e. “Giffords Score”). On this scorecard each state is assigned a “school grade” (i.e. A to F) for their gun laws with the strictest states getting an A and least-strict states getting an F.

I have one issue with the Giffords Score. The process by which the grades are assigned is (as far as I can tell) opaque. That’s not really surprising as there is judgement involved, but it does leave us open to some feedback loops. Still, it’s the best that we have, so let’s run with it.

To view the Gifford’s Score, visit this link: https://giffords.org/lawcenter/resources/scorecard/

Correlating Gun Laws to Murders, Suicides and Accidental Deaths

For the purposes of this analysis, I converted each state’s Giffords Score into the standard grade point. So, a state with an “A” gets a 4.0 and a state with an “F” gets 0.0.

I then found the “best possible” data for homicides and suicides by state. (I was unable to find state level data for accidental deaths.) By comparing the data with the Giffords Score (specifically by calculating the Spearman’s Rank Correlation Coefficient), we can see if there is a correlation between the two.

A Spearman’s Rank Correlation Coefficient (our data is not a normal distribution) is a value between -1 and 1 that shows how tightly correlated two values are. A value of 1 indicates perfect correlation (such as “x = y” or “x = 2y”). A value of -1 indicates an inverse correlation (i.e. “x = -y”) and a value of 0 indicates no correlation. The further you get from zero, the more highly correlated two numbers are.

There is a rule of thumb for how to interpret the Spearman’s Coefficient (SC). Based on the following “value ranges”, we infer the following:

  • SC > 0.9 – Very high correlation
  • 0.7 < SC <= 0.9 – High correlation
  • 0.5 < SC <= 0.7 – Moderate correlation
  • 0.3 < SC <= 0.5 – Low correlation
  • -0.3 <= SC <= 0.3 – No correlation
  • -0.5 <= SC < -0.3 – Low inverse correlation
  • -0.7 <= SC < -0.5 – Moderate inverse correlation
  • -0.9 <= SC < -0.7 – High inverse correlation
  • SC < -0.9 – Very high inverse correlation

Accidental Deaths

I was unable to find any state-level statistics regarding gun related accidents. Pre-pandemic, the number of deaths hovered around 492 per year, with a sharp spike during lockdowns (often involving children). This represents a rate of about 0.16 deaths per 100,000 people.

I think it’s safe to say that without a gun in a home, the chances of an accidental shooting occurring in that home is substantially reduced. Research by the Harvard Injury Control Research Center has shown (https://www.hsph.harvard.edu/hicrc/firearms-research/gun-threats-and-self-defense-gun-use/):

  • States with more guns have more unintentional firearm deaths.
  • Unsafe gun storage correlates to more unintentional firearm deaths.
  • Youth killed in gun accidents are most commonly shot by another youth. (Older adults are at a lower risk of accidental firearm deaths and they usually accidentally shoot themselves.

It seems probable to me that reducing the number of homes with guns would reduce the number of accidental deaths. Requiring that guns be stored safely (and enforcing that requirement) and requiring training on safe gun handling for gun owners would also seem likely to reduce the number of accidental deaths.

Suicide

According to the Centers for Disease Control (https://www.cdc.gov/nchs/pressroom/sosmap/suicide-mortality/suicide.htm), there were about 48,137 suicides in 2019. The suicide rate varies widely between the states with New Jersey having the lowest suicide rate (8.0 per 100,000) and Wyoming having the highest (29.3 per 100,000).

Analysis of the data shows a high correlation between gun ownership rates and suicide rates (0.74). It also shows a moderate inverse correlation between a state’s Giffords Score and the suicide rate (-0.60). Simply put, more guns and fewer gun regulations correlate to more suicides.

This is not surprising as guns are often seen as a quick and painless way to commit suicide (a common misconception). It seems plausible that, when a gun is not available, individuals contemplating suicide either elect to forgo a painful alternative or make the attempt and are not successful.

These correlations imply that increasing gun regulation and the resulting reduction in the gun ownership rate would significantly reduce the suicide rate.

Murder (including non-negligent manslaughter)

According to the U.S. Federal Bureau of Investigation (https://ucr.fbi.gov/crime-in-the-u.s/2019/crime-in-the-u.s.-2019/tables/table-1), there were about 16,425 murders in 2019. Maine had the lowest murder rate (1.6 per 100,000 people) while Louisiana had the highest (11.7 per 100,000 people).

Analysis of the data showed no correlation between gun ownership rates and homicide rates (0.19). Nor does it show any correlation between a states Giffords Score and its homicide rate (-0.17). In short, the data does not support the assertion that gun control and the resulting reduction in the gun ownership rate would yield a measurable reduction in the homicide rate.

I also investigated mass shootings. There are a wide variety of definitions of mass shootings. I used the list (for 2019) provided by Wikipedia (https://en.wikipedia.org/wiki/List_of_mass_shootings_in_the_United_States_in_2019) which requires that an event meet two or more definitions to be included. Using this list there were about 425 mass shootings in 2019 with 458 victims (not including perpetrators). Mass shootings accounted for about 2.8% of murder victims.

Analysis of the data showed no correlation (-0.05) between gun ownership rates and the rate of mass shootings in a state (states with more guns had slightly fewer mass shootings). It also showed no correlation (0.01) between the Giffords Score and the number of mass shootings. Repeating the calculations using victim counts instead of mass shooting events yielded similar results (0.04 and -0.10, respectively). Gun control does not appear to influence the number or lethality of mass shootings.

Real World Considerations

Over the years, I have heard many arguments about what the Second Amendment means. While some might find these debates fun, the answer is astonishingly simple. The Second Amendment means whatever the Supreme Court says it means. This court seems to take a rather expansive view of the Second Amendment.

As a result, while it is possible for congress, the states and even localities to enact gun control legislation, there are significant limits on what that legislation can do. From a practical point of view, New Jersey and California are probably about as stringent as we can get with the current makeup of the Supreme Court and the Second Amendment.

We also live in a country where there are about as many guns as there are people, including a huge number of semi-automatic and concealable guns. While it may be possible to slow the rate at which new guns enter the market and place limits on who can own a gun, it would be much harder to recover existing guns. This, coupled with the durability of guns, limits the efficacy of gun control.

Conclusions

Additional gun control measures that reduce the gun ownership rate can be expected to have a small impact on the number of accidental deaths and a measurable impact on the number of deaths due to suicide. As suicide is the dominant form of gun deaths, efforts to promote gun control are worthwhile.

Gun control measures are unlikely to significantly impact the homicide rate, the rate of mass shootings, or the lethality of mass shootings. Alternative measures should be sought to address these issues.