According to a CBS news post on Nov. 5, in just over a year there have been 11 mass shootings that have left 85 people dead in the U.S. The timeline starts with the Colorado movie massacre that killed 12 and ends with the Los Angeles airport shooting.
In most of these cases, there was no defense for the civilians who were attacked. Carrying concealed handguns could aid in ending public shooting sprees.
Concealed handguns are an effective form of self-defense most of the time. An autumn 1995 peer-reviewed study by Gary Kleck, published in the Journal of Criminal Law and Criminology, found that when someone draws a concealed gun in self-defense, the criminal simply retreats 55.5 percent of the time.