At Real Clear Investigations: How the FBI Undercounts Armed Citizen Responders to Mass Killers — and
John Lott - Crime Prevention Research Center | Published on 9/18/2022
The Bureau reports that only 11 of the 252 active shooter incidents it identified for the period 2014-2021 were stopped by an armed citizen. An analysis by my organization identified a total of 281 active shooter incidents during that same period and found that 41 of them were stopped by an armed citizen.
That is, the FBI reported that 4.4% of active shooter incidents were thwarted by armed citizens, while the CPRC found 14.6%.