GALVESTON, Texas — The frequency of violent incidents involving guns in the United States in recent years has shed light on an incredibly troubling trend. After a shooting occurs, the political floodgates open and while some call for tougher gun reform laws, others point to mental illness as a rational explanation as to why someone would commit such senseless violence. Surprisingly, a long-term study finds that mental illness is not an accurate predictor of gun violence.

Researchers out of the University of Texas’ Medical Branch in Galveston conclude that the primary factor contributing to most mass shooting and smaller gun violence-related incidents is access to guns. They reached this conclusion after analyzing the association between gun violence and mental health in a group of 663 young adults in Texas.

Rather than finding a clear association with mental health problems, researchers calculated that individuals who had access to guns were more than 18 times more likely to have threatened someone with a firearm than someone with no such access. On the other hand, individuals who showed signs of hostility and aggression were only about 3.5 times more likely to threaten someone with a gun.

“Counter to public beliefs, the majority of mental health symptoms examined were not related to gun violence,” says lead study author Dr. Yu Lu in a statement. “These findings have important implications for gun control policy efforts.”

Study participants were asked if they own any guns, and if so, how frequently those guns are used. Additionally, participants were asked about their own experiences with a number of mental health conditions and factors. Such factors include depression, stress, anxiety, hostility, impulsivity, PTSD, borderline personality disorder, and any prior mental health treatment.

According to The Centers for Disease Control, an estimated 75,000 to 100,000 Americans are injured by firearms each year, and between 30,000 and 40,000 Americans are killed annually.

“Much of the limited research on gun violence and mental illness has focused on violence among individuals with severe mental illnesses or rates of mental illness among individuals arrested for violent crimes,” Lu explains. “What we found is that the link between mental illness and gun violence is not there.”

The study is published in the scientific journal Preventative Medicine.

This article was first published on July 3, 2019.