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.
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. The disclaimer here is that correlation is not causation. But correlations can be suggestive.
"The map overlays the map of firearm deaths above with gun control restrictions by state," explains Florida. "It highlights states which have one of three gun control restrictions in place - assault weapons' bans, trigger locks or safe storage requirements. Firearm deaths are significantly lower in states with stricter gun control legislation. Though the sample sizes are small, we find substantial negative correlations between firearm deaths and states that ban assault weapons (-.45), require trigger locks (-.42) and mandate safe storage requirements for guns (-.48)."
10. Gun control, in general, has not been politically popular.
Since 1990, Gallup has been asking Americans whether they think gun control laws should be stricter. The answer, increasingly, is that they don't.
"The percentage in favor of making the laws governing the sale of firearms 'more strict' fell from 78% in 1990 to 62% in 1995, and 51% in 2007," Gallup reported after the Tucson, Ariz., shooting in 2011. "In the most recent reading, Gallup in 2010 found 44% in favor of stricter laws. In fact, in 2009 and again last year, the slight majority said gun laws should either remain the same or be made less strict."