Garen Wintemute, an emergency medicine physician at U.C. Davis, says more restricting of gun purchases will prevent mentally ill people from engaging in future firearm violence, including mass shooting catastrophes such as those that occurred at Newtown, Connecticut, Virginia Tech in Virginia and Aurora and Columbine in Colorado - though those incidents had little in common except mental illness by the murderers.

In a time when American culture is criticized for having too many people in jail for misdemeanors, Wintemute wants to put anyone with a misdemeanor in jail if they own a gun.

He claims the US has 5 percent of the world’s population but 40 percent of all firearms that are in civilian hands. In addition, he believes that the US Constitution's Second Amendment has allowed too many firearms to be available for too many people. Wintemute says things like the “Stand Your Ground” laws, created to protect victims of domestic abuse and enacted at the state level to affirm that a person may justifiably use force in self- defense when there is reasonable belief of an unlawful threat, are instead dangerous experiments that have been used to legitimize shootings that he considers murder. Colorado, Connecticut and Virginia do not have a Stand Your Ground law.

"To reduce the number of deaths and injuries from firearms in the United States, we need to develop policies that require background checks for all firearm purchases, including private-party sales — the most important source of firearms for criminal buyers and others who are prohibited from purchasing guns," said Wintemute, also director of the UC Davis Violence Prevention Research Program and inaugural Susan P. Baker-Stephen P. Teret Chair in Violence Prevention at UC Davis. "We need to prevent individuals with a previous conviction for a misdemeanor violent crime, such as assault and battery, from purchasing or possessing a firearm. We also need to develop better data and criteria that allow us to distinguish between those with a treatable mental disorder who do not have a history of violence from those with a history of violence or substance abuse." 

Wintemute emphasizes more bans as a solution.  He claims that among persons who purchase firearms legally, those with a previous conviction for a misdemeanor violent crime are roughly nine times as likely as those with no criminal history to be arrested for a violent crime later. For those with two or more such prior convictions, he found the risk increases by a factor of 10 to 15. In addition, studies have shown that firearm owners who abuse alcohol are more likely than other owners to engage in violence-related firearm behavior.  

"It may be impossible to predict the next mass shooting incident, and we cannot expect interventions designed for specific circumstances to eliminate the risk of firearm violence. But we can change our firearms laws, based on existing evidence, to reduce harm and better ensure public safety,” he said. “Some 40 percent of all firearm transactions, for example, involve private-party sellers, who are not required to keep records and cannot obtain a background check. We need policies that prevent these quick, anonymous and undocumented sales. We also need policies that deny gun purchases to those who we know are at high risk for violence.

“We know that comprehensive background checks and expanded denial criteria are feasible and effective, because they are in place in many states and have been evaluated. In California, the denial policy reduced the risk of violence and firearm-related crime by 23 percent among those whose purchases were denied. But we need to broaden these and other effective state-level regulations to eliminate the flow of firearms from states where laws are lax to states where laws are stricter.” 

Wintemute says proposals for comprehensive background checks and denials for misdemeanor violence and for alcohol abuse enjoy broad public support, including among firearm owners. Survey data was gathered by Wintemute and he says he also looked at a series of public polls conducted for the Mayors Against Illegal Guns. 

“While the individual circumstances of the mass shooting massacres in the U.S. are different, we can only change the outcome if we confront the challenge of unchecked and easy access to firearms,” Wintemute said. “Strengthening our background check and denial policies for firearm purchases will not eliminate firearm violence, but they can reduce it.”

 Published in the New England Journal of Medicine.