[Epistemic status: I think I probably wrung the right conclusions out of this evidence, but this isn’t the only line of evidence bearing on the broader gun control issue and all I can say is what it’s consistent with. Content warning for discussion of suicide, murder, and race]

I.

From a Vox article on America’s Gun Problem, Explained: “On Wednesday, it happened again: There was a mass shooting — this time, in San Bernardino, California. And once again on Sunday, President Barack Obama called for measures that make it harder for would-be shooters to buy deadly firearms.”

Then it goes on to say that “more guns mean more gun deaths, period. The research on this is overwhelmingly clear. No matter how you look at the data, more guns mean more gun deaths.” It cites the following chart:

…then uses the graph as a lead in to talk about active shooter situations, gun-homicide relationships, and outrage over gun massacres.

Did you notice that the axis of this graph says “gun deaths”, and that this is a totally different thing from gun murders?

(this isn’t an isolated incident: Vox does the same thing here and here)

Gun deaths are a combined measure of gun homicides and gun suicides. Here is a graph of guns vs. gun homicides:

And here is a graph of guns vs. gun suicides:

The relationship between gun ownership and homicide is weak (and appears negative), the relationship between gun ownership and suicide is strong and positive. The entire effect Vox highlights in their graph is due to gun suicides, but they are using it to imply conclusions about gun homicides. This is why you shouldn’t make a category combining two unlike things.

II.

I am not the first person to notice this. The Washington Examiner makes the same criticism of Vox’s statistics that I do. And Robert VerBruggen of National Review does the same analysis decomposing gun deaths into suicides and homicides, and like me finds no correlation with homicides.

German Lopez of Vox responds here. He argues that VerBruggen can’t just do a raw uncontrolled correlation of state gun ownership with state murder rates without adjusting for confounders. This is true, although given that Vox has done this time and time again for months on end and all VerBruggen is doing is correctly pointing out a flaw in their methods, it feels kind of like an isolated...

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