Here is one correlation between state gun laws and mass shootings
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"(CNN) - An analysis performed for CNN found that states that have enacted magazine restrictions are associated with fewer mass shooting events.
'Whether a state has a large capacity ammunition magazine ban is the single best predictor of the mass shooting rate in that state,' said Michael Siegel, a community health science professor at Boston University, who conducted the analysis. These states are associated with a 63% lower rate of mass shootings, according to his analysis."
Author: Sam Petulla.
Outlet: CNN Politics.