New research puts the 'good guy with a gun' idea to rest: Loose concealed-carry laws are linked to more firearm homicides

• A new study found that states with looser concealed-carry gun laws have higher rates of gun homicide.
• The results also showed that higher levels of gun ownership are associated with more mass shootings.
• The study suggests the US could reduce gun violence by lowering levels of gun ownership and passing stricter concealed-carry laws.

The "good guy with a gun" theory goes like this: If more well-intentioned people carry guns, there's a higher chance of stopping a violent shooter.

Unfortunately, that's not how it works in real life, according to new research published in the journal Justice Quarterly. The study found that laws allowing more people to carry guns in public are associated with a rise in gun violence. The results also showed that the higher a state's gun-ownership rate, the more likely a mass shooting is.

Emma Fridel, an assistant professor at Florida State University who authored the study, measured the affects of gun ownership rates and concealed-carry laws in all 50 states from 1991 to 2016. She controlled for other factors that might influence mass shooting and homicide rates, like unemployment rates, poverty levels and states' mental health expenditures.

Her findings show that looser concealed-carry laws had little impact on mass shootings and increased a state's gun homicide rate by 11%. Higher rates of firearm ownership overall, meanwhile, was associated with a 53.5% increase in the likelihood of a mass shooting.

"In popular culture, you hear people saying, 'Oh, if I had a gun and I was at that Wal-Mart, I could've stopped that shooting,'" Fridel told Business Insider "But that's probably not true."

Concealed-carry laws have become more prevalent

In 2015, 56% of Americans said they believed that increased gun-carrying in public — if carriers passed criminal background checks and training courses — would make the country safer.

Changing state laws have reflected that belief: While just 15 states had permissive concealed-carry policies in the early 1990s, 41 states had implemented them as of 2018. For instance, Ohio passed a law in 2017 allowing people with concealed-carry permits to bring firearms into daycare centers and company parking lots.

Meanwhile, mass shootings and firearm deaths have increased, particularly in the last decade. The US saw 418 mass shootings and 15,395 deaths due to gun violence in 2019 (not counting suicides), compared to 269 mass shootings and 12,390 deaths in 2014.

Fridel's research showed that conceal-carry laws are a stronger predictor of firearm homicides than gun ownership.

"Concealed-carry laws are such a strong effect that it drowns the firearm ownership rate out," she said. It was only when she eliminated concealed-carry legislation as a factor in the analysis that she also found a positive correlation between general gun ownership and gun homicides.

Mass shootings 'disproportionately' drive gun laws

Even though mass-shooting deaths represented just a tiny fraction of total firearm deaths in 2019 (465 out of the 39,485, according to the Gun Violence Archive), the horror of mass shootings means these events have "disproportionately influenced the public discourse on firearms ownership and legislation," according to Fridel.

A 2019 study found that each mass-shooting incident increased the total number of firearm-related bills introduced in a given state by 15%.

Fridel's study suggests a "two-pronged approach" for combating gun violence in the US overall, mass shooting or otherwise. The first solution is to reduce gun ownership, potentially via universal background checks and increased requirements for permits. The second is simply to make concealed-carry permits more difficult to get.