An analysis of mass shootings in the United States over the past 30 years found no examples where an armed civilian ended an attack or any evidence that places that do not allow guns invite mass shootings. Furthermore, research has indicated that students who possess guns at college are more likely than their peers to engage in risky conduct, suggesting that arming students could have substantial risks. View Full Article: http://mediamatters.org/blog/2015/02/19/no-evidence-for-joe-scarboroughs-claim-that-gun/202567