There were absolutely no articles, blogs, or studies that I could find that suggested causation at all. Below is a list of articles that attempt to prove or disprove correlation.
This blog post attempts to show correlation, if any, on a scatter plot between gun ownership and murder / crime rates.
From the article:
It has the following data for all 50 states (except Florida, which
does not submit the data for some reason):
- Brady Score (how much gun control a state has)
- Murder Rate per 100k population
- Firearm murder rate per 100k population
- Firearm Murder %
and I added
- Violent Crime Rate per 100k population
The following are the scatter plots that he generated, which (in the author's analysis and findings) show no statistical correlation between gun ownership and firearm murder or crime rate.
The original source for the article is another blog post that can be found here.
Looking at US data, another blogger did scatter plot analysis using source data from the About.com US Liberal Politics page and the Gun violence in the United States Wikipedia page. He concludes that:
There is literally 0 correlation between how many people own firearms,
and the homicide rate with firearms, or overall homicide rate as below
graphs and correlation coefficients illustrate.
His graphs are shown here:
In yet another scatterplot analysis of correlation between gun ownership and murder rate by country (again, using Wikipedia as the source), the author find a negative correlation between gun ownership and rate of homicide. He also makes a comment that these statistics aren't very helpful in the debate. From the article:
If all countries are included in the plot, there is a negative
correlation between gun ownership and rate of homicide. Only when the
plot is limited to OECD countries (with the outliers of US and Mexico
included), does a very small positive correlation appear.
Because of the many uncontrolled variables involved in comparisons
between countries, I don’t believe such statistics can help the case
for or against gun control. I’m posting them here to counter the
claims by advocates of increased governmental gun control that the
statistics legitimise their preference.
A separate study entitled Would Banning Firearms Reduce Murder and Suicide? A Review of International and Some Domestic Evidence done by Don B. Kates (an American Criminologist and Attorney) and Gary Mauser (a Canadian Criminologist), was published in Volume 30, Number 2 of the Harvard Journal of Law & Public Policy (pp. 649-694). The authors in this article found that there is no correlation between gun ownership and murder.
From the article:
The non‐correlation between gun ownership and murder is reinforced by
examination of statistics from larger numbers of nations across the
developed world. Comparison of “homicide and suicide mortality data
for thirty‐six nations (including the United States) for the period
1990–1995” to gun ownership levels showed “no significant (at the 5%
level) association between gun ownership levels and the total homicide
rate.” Consistent with this is a later European study of data from 21
nations in which “no significant correlations [of gun ownership
levels] with total suicide or homicide rates were found.”
The authors then go on to say that they found a negative correlation between gun ownership and violent crime, meaning that populations with higher gun ownership had fewer incidents of violent crime. From the article:
The same pattern appears when comparisons of violence to gun ownership
are made within nations. Indeed, “data on firearms ownership by
constabulary area in England,” like data from the United States, show
“a negative correlation,” that is, “where firearms are most dense
violent crime rates are lowest, and where guns are least dense violent
crime rates are highest.”
Another book entitled More Guns, Less Crime, written by John Lott, studies crime data for every county in the United States during 29 years from 1977 to 2005 and finds no correlation between gun ownership and murder and concludes that allowing concealed handguns decreases violent crime rates.
The wikipedia page (linked to above) for the book has a slew of papers that argue for and against his conclusions.
The Statistics section of the Gun Politics Wikipedia page references a slew of reports, studies, and anecdotes against gun control.
There are several sites that display or visualize data, but whose authors don't make any claims or assessments on correlation or causality whatsoever. The Guardian published data in an article entitled Gun homicies and gun ownership listed by country that can be downloaded an analyzed. They also have an interactive heat map that displays the following data:
- Average firearms per 100 people
- Homicide by firearm rate per 100,000 population
- % of homicides by firearm
This is a screenshot of the heatmap:
I took a (very) shallow dive into the data, looking at a 3-4 countries from each continent and there doesn't seem to be much correlation between ownership rates and murder rates. One commenter on the article makes an interesting point that we can't use the univariate solution of Gun Control to solve a multivariate problem of murder. He says:
If the rate of gun ownership is a determinant of the gun murder rate,
how does one explain the gun ownership rates in Mexico (15 guns /100
and 9.97 murders/100k) and Jamaica (8.1 guns/100 and 39.4 murders
/100K) and the very high gun murder rates? Guatemala has a gun
ownership rate of 13.1/100 and a murder rate of 34/100k.
The US has 88.8 guns/100 and 2.97 murders/ 100k.
Univariate solutions for multivariate problems are unsatisfying.
On the other side of the debate, the article entitled Rates of Household Firearm Ownership and Homicide Across US Regions and States, 1988–1997 concludes as follows:
Although our study cannot determine causation, we found that in areas
where household firearm ownership rates were higher, a
disproportionately large number of people died from homicide.
FactCheck.org reviewed studies in 2008 and posted Violent Crimes and Handgun Ownership. They looked at a study by David Hemenway (director of the Harvard Injury Control Research Center and the Harvard Youth Violence Prevention Center), who reviewed commonly cited research from peer-reviewed journals. From the FactCheck.org article:
It found that studies of the United States or U.S. cities, states and
regions "generally find a statistically significant gun
prevalence-homicide association." The report said that the evidence
from such "U.S. cross-sectional studies is quite consistent … where
there are higher levels of gun prevalence, homicide rates are
substantially higher, primarily due to higher firearm homicide rates."
With regard to a causal relationship, FactCheck.org says:
That’s not to say that taking the guns away from such areas would
necessarily lead to a reduction in the murder rate. Such studies have
shown a statistically significant relationship between guns and murder
but not a causal one.
Disclaimer: I haven't personally reviewed the original sources or the analysis behind the sources I'm referencing. I'm not making an argument, one way or the other, as to whether or not I agree with the findings in these articles. I posted these because I think the format and nature of the findings in are specifically relevant to the original question.
Disclaimer 2: I listed many more articles that show little to no correlation, because it was more difficult to find ones that demonstrated a significant correlation. I am happy to add references to more articles that show positive correlation (or even causation) if you post them in the comments.