https://www.sciencedaily.com/releases/2022/09/220920115436.htm

The studyexamined two aspects of policy changes: the overall impact on gun violence when states changed their laws for civilians carrying concealed firearms from more to less restrictive ones and, secondly, whether less restrictive measures -- known as "shall issue" laws -- containing specific safety and screening provisions influenced gun violence outcomes.

The study found that moving to less restrictive laws was associated with a 24 percent increase in the rate of assaults with firearms (12.75 per 100,000) when individuals convicted of violent misdemeanors were eligible to obtain concealed-carry licenses. The researchers also found that states with shall issue laws that had live-fire firearm safety training requirements did not see the significant increases in firearm assaults that were estimated for states that lacked such requirements.