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Johns Hopkins Center for Gun Violence Prevention and Policy


Licensing laws or Permit-to-Purchase (PTP) laws require an individual who wants to purchase a firearm to apply for a license at a local law enforcement agency. The application may include a background check, fingerprinting, and potentially evidence of handgun safety training.

PTP laws are in effect in 9 states and the District of Columbia: Connecticut, Hawaii, Illinois, Iowa, Maryland, Massachusetts, New Jersey, New York, and North Carolina. Center researchers have determined the impact of licensing on a number of outcomes, including homicide, suicide, shootings of law enforcement officers and intimate partner homicide.

Key Statistic

After Missouri repealed its licensing law in 2007, the state saw a 16.1 percent increase in firearm suicide and a 25 percent increase in firearm homicide. Following Connecticut’s implementation of a licensing law, the state’s firearm homicide rate declined 40 percent and the firearm suicide rate declined 15.4 percent.[1]

“Requiring a license or permit to purchase a handgun reduces firearm homicides and suicides, as well as trafficking and shootings of law enforcement officers. It is one of the most effective policies we have to reduce gun violence.”

– Cassandra Crifasi, Center Deputy Director

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[1] Crifasi et al. Effects of changes in permit-to-purchase handgun laws in Connecticut and Missouri on suicide rates. Prev Med. 2015 Oct;79:43-9. Rudolph et al. Association Between Connecticut's Permit-to-Purchase Handgun Law and Homicides. Am J Public Health. 2015 Aug;105(8):e49-54. Webster et al. Effects of the repeal of Missouri's handgun purchaser licensing law on homicides. J Urban Health. 2014 Apr;91(2):293-302).