negative effect on violent crime rates with passage of shall-issue laws. A 2017 study in Applied Economics Letters found that property crime decreased in Chicago after the implementation of the shall issue concealed carry law. A 2014 Applied Economics Letters study found states with more permissive conceal carry laws had lower murder rates than states with restrictive laws. Another 2014 study found that RTC laws by state significantly reduce homicide rates. In 1996, economists John R. Lott, Jr. and David B. Mustard analyzed crime data in all 3,054 counties in the United States from 1977 to 1992, finding counties that had shall-issue licensing laws overall saw murders decrease by 7.65 percent, rapes decrease by 5.2 percent, aggravated assaults decrease by 7 percent and robberies decrease by 2.2 percent. The study was widely disputed by numerous economists. The 2004 National Academy of Sciences panel reviewing the research on the subject concluded, with one dissenting panelist, that the Lott and Mustard study was unreliable. Georgetown University Professor Jens Ludwig, Daniel Nagin of Carnegie Mellon University and Dan A. Black of the University of Chicago in The Journal of Legal Studies, said of the Lott-Mustard study, "once Florida is removed from the sample, there is no longer any detectable impact of right-to-carry laws on the rates of murder and rape". A 2022 study examining the Sullivan Act of 1911 found that the law had no impact on overall homicide rates, reduced overall suicide rates, and caused large and sustained decrease in gun-related suicide rates. Firearms permit holders in active shooter incidents In 2016 FBI analyzed 40 "active shooter incidents" in 2014 and 2015 where bystanders were put in peril in on-going incidents that could be affected by police or citizen response. Six incidents were successfully ended when citizens intervened. In two stops citizens restrained the shooters, one unarmed, one with pepper spray. In two stops at schools, the shooters were confronted by teachers: one shooter disarmed, one committed suicide. In two stops citizens with firearms permits exchanged gunfire with the shooter. In a failed stop attempt, a citizen with a firearms permit was killed by the shooter. In 2018 the FBI analyzed 50 active shooter incidents in 2016 and 2017. This report focused on policies to neutralize active shooters to save lives. In 10 incidents citizens confronted an active shooter. In eight incidents the citizens stopped the shooter. Four stops involved unarmed citizens