Ezra Klein lays out 12 of them. Two of his points:
8. More guns tend to mean more homicide.
The Harvard Injury Control Research Center assessed the literature on guns and homicide and found that there’s substantial evidence that indicates more guns means more murders. This holds true whether you’re looking at different countries or different states. Citations here.
9. States with stricter gun control laws have fewer deaths from gun-related violence.
Last year, economist Richard Florida dove deep into the correlations between gun deaths and other kinds of social indicators. Some of what he found was, perhaps, unexpected: Higher populations, more stress, more immigrants, and more mental illness were not correlated with more deaths from gun violence. But one thing he found was, perhaps, perfectly predictable: States with tighter gun control laws appear to have fewer gun-related deaths. States with tighter gun control laws appear to have fewer gun-related deaths. The disclaimer here is that correlation is not causation. But correlations can be suggestive . . . .