The topic of gun control has once again been raised in the US.  While a plain reading of the Constitution or a respect for human rights would render the discussion moot, as the right to keep and bear arms is both unreservedly protected by the Constitution and furthermore is necessary to exercise the fundamental human right of self defense, the debate will nevertheless continue.  The proponents of gun control claim that it is a necessary step for achieving public safety, so a part of the debate over the issue will, as always, revolve around the relationship between guns and violence.  The pro-gun-control side will tout statistics that purport to show a positive relationship between gun ownership and violence, while the anti-gun-control side will tout statistics that purport to show a negative relationship between the two.  As such, I thought it would be interesting to look at this relationship from multiple angles, to see how it changes based on what is being considered.  From what I had seen in the past, the most significant factor affecting how the relationship appears is the set of countries under consideration in the data-set.  Since the US is a populous, developed, American country, I decided to look at the same topics with data from three sets of countries: populous countries (the 20 most populous, accounting for over 69% of the world’s people), developed countries (as defined by the IMF) and American countries (those in North and South America, over 10M in population – which accounts for 95% of the people of the Americas).  All data on guns and violence in these countries I got from GunPolicy.org (source), an organization run by the University of Sydney with funding from the UN.  For each topic and data-set I created a scatter plot and applied a best-fit linear trend line.

First up, let’s consider gun ownership and homicide.  Homicide is the most violent of crimes, and the crime most likely to be accurately reported in every nation (lesser crimes are easier for criminals to hide and easier for authorities to ignore), so in addition to being a topic of great concern in its own right it is a good proxy for violent crime in general.

It is apparent that any supposed relation between gun ownership and homicide depends greatly on the data-set used.  Comparing populous  nations yields a weak negative correlation, comparing developed nations yields a strong positive correlation, and comparing American nations yields a moderate negative correlation.  The second chart would of course be a favorite of gun-control advocates, while the third would be a favorite of gun-control opponents.  Personally, I think the first chart is probably the most significant, as it encompasses the largest number of people for consideration.  Which chart you consider most illuminating will probably depend in part upon which set of nations you think the US is most properly compared to.

The article should end there, but the topic of gun ownership and its relationship to violence will often see debaters marshaling statistics on other topics than general violent crime.  A favorite is to consider not homicide in general, but gun homicide in particular.  While I feel this is disingenuous, as homicide is homicide and the victim probably doesn’t much care about the method after the fact, it is still a topic that will be raised and thus is worthy of consideration in our analysis.

Unsurprisingly, there is a more positive correlation between gun ownership and gun homicide.  This makes sense, as when a tool is more commonly available it will be more commonly used.  Of course, where guns are more common we would expect guns to be more likely to be used both to defend against crimes as well as commit them, so any correlations here seem to me to be of little value in comparison to correlations with total crime rates.  But there is obvious value here for those pushing gun control, so this highly parsed category will be a common sight in gun control debates.  I will say it is surprising to see that there is still a slight negative correlation between guns and gun homicides in the Americas, but since the Americas are the most violent continents in the world (at least as far as private crime is concerned), this does make sense.  It should also be noted that not all countries tabulate data on method of homicide (see tables below), so what correlations appear here are a bit less accurate than those apparent in the general homicide charts above.  Tables of the gun and homicide data are below for those interested in the specific numbers.

Populous Nations

Developed Nations

American Nations (Over 10M Population)

But that’s not all!  The debate on guns and violence frequently will see people reference suicides and accidental deaths as well.  While a free society has no duty (or even right) to protect people from themselves, so therefor suicides and accidents should be of no consideration in policy making, nevertheless this is of concern to those who wish to control guns, so we’ll consider it here as well.  First up we’ll take suicides, both the general rate and then the gun suicide rate.

With the exception of developed nations, among which there seems to be no correlation, there is a positive correlation between gun ownership rates and suicide rates.  And when considering only gun suicides, we see the strongest and most unambiguous positive correlation among all the topics considered in this article.  I think it is safe to say that guns are the favorite tool for suicide among suicidal gun-owners, which makes sense from the perspective that it is quick, easy, and effective, albeit it is probably not the least messy way to go and so not the most considerate to the clean-up crew.  An interesting note is that suicide rates tend to be higher in nations with lower homicide rates, which may imply that there are deeper cultural factors at play in all of this.  At any rate, while controlling guns would certainly reduce gun suicides, the likelihood that such measures would reduce suicides in general seems low.  But since suicides outnumber homicides in many nations (and in all developed nations), it is not surprising for the issue of suicides to be brought up when making the case for gun control, in order to bolster the numbers of people who die by guns.

Finally there is the issue of accidental gun deaths.  The numbers are generally quite low in comparison to homicide rates and suicide rates, but accidental gun deaths are still frequently mentioned during discussions of the topic of gun control, so I thought to include them.

The correlations here are all weak, which would indicate to me that while the proliferation of guns increases the opportunity for accidents it also increases familiarity with how to safely handle guns.

The take-away from all this is that there is not a clear and decisive answer in the data to the question of whether gun proliferation is related to violence, and conversely whether gun control would increase safety.  Depending on how one looks at the situation, one can get numbers to justify either position in this debate.  I guess this is why it has been said that “there are three kinds of lies: lies, damned lies, and statistics”.