Gun control and gun ownership has no effect on homicide rates either way. Six charts that plot freedom and homicide rates versus gun ownership and gun control for 150+ countries.

I got tired of all the Facebook posts I saw that compared two cherry picked countries. Nobody could present more data when asked. So I decided to do some research to find out on my own. My preliminary research left me disheartened. When I compared a few countries, it seemed the US had all of the murders and none of the freedom. After a few days, I found the resolve to dig further and found way more data. (Incidentally, it seems sources that were pro gun-control (gunpolicy.org, bradycampaign.org) made it difficult to download data.) I wanted a breakdown by country, because it is easy to transport a gun between cities or states, but more difficult to transport between countries.

Gun Ownership vs. Homicide Rate

Gun deaths or gun homicides? I decided on homicides because of course more guns = more gun deaths (I also saw the charts showing that). Most of those are suicides. While it's tragic, I'm not really worried about random suicides compared to random shootings. There are many ways to suicide, and taking away guns won't stop that problem. More cars = more car deaths. So what? What about gun homicides vs. homicides? After reading about mass stabbings in China (30+ deaths!) and Japan, it becomes clear people are worried about homicides, not just gun homicides. Also, how do you test the theory that "more guns prevents crime"? So I went with homicide rate. It turns out there isn't a strong relationship between guns and homicides either way.

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Gun Ownership vs. Freedom (FreedomHouse)

What about "guns prevent tyrrany"? It seems they slightly do. (Lower freedom score is better.)

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Gun Ownership vs. Freedom (FreeTheWorld)

Higher scores are better in this one.

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Gun Control vs. Homicide Rate

I finally found a source that quantifies gun control laws, not just the guns per capita! Some owners might have 100 guns. It shows an ever so slight increase in homicides with less gun control.

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Gun Control vs. Freedom (FreedomHouse)

This shows less gun control = more freedom. (Both scales are backwards.)

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Gun Control vs. Freedom (FreeTheWorld)

This shows absolutely no relation between gun control and freedom.

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Sources

Here is a Google Sheet and Excel spreadsheet with all of the data and sources to generate your own chart.

Google Sheet,
Excel