Rep. Mike Hill (R-Pensacola) wants to repeal gun safety legislation passed in Florida after the deadly Marjory Stoneman Douglas school shooting last year in Parkland. He says the measures, including a state ban on bump stocks, the so called red flag law and a provision raising the age to purchase a rifle violate the Second Amendment. He also says firearms aren’t the cause of mass shootings. Instead he points his finger at the use of psychotropic drugs, like Ritalin.

“First of all it starts at a very early age in school, just because a hyper active child is now diagnosed with ADHD, when back in my day in the 60s you were simply told to go sit in time out or to calm down, Hill says. “Now they give them drugs—psychotropic drugs—Ritalin—to change their behavior. And then those drugs are continued as they get older. Because it’s almost like once they get on it they can’t stop,” Hill says.

Hill claims that’s what the majority of mass shooters have in common.

“Whenever you see or you study a mass shooting that has taken place those young men have either been on, or are currently on, prescribed psychotropic drugs. That is the issue,” Hill says.

Hill’s statement closely mirrors an article by the pro-gun publication AmmoLand that’s been circulating on social media in the last few weeks.

The article reads: “The signal (sic) largest common factor in all of these incidents is the fact that all of the perpetrators were either actively taking powerful psychotropic drugs or had been at some point in the immediate past before they committed their crimes.”

But Jillian Turanovic, a professor at Florida State University says that claim doesn’t sound accurate.

Credit via Florida State University Criminology Department / via Florida State University Criminology Department Jillian Turanovic received a grant from the National Institute of Justice to build a database on all mass shootings that have occurred in the U.S. since 1980.

Turanovic is building a database on all mass shootings that have occurred in the U.S. since 1980. She says if overprescribing psychotropic drugs like Ritalin was a cause of shootings, researchers would expect to see the number of mass shootings increase along with an increase in the use of the drugs. But that’s not what she sees.

“Given the social constructure of mass shootings and their visibility in recent years I think most people would think that they are in fact increasing but our data don’t really suggest that’s the case. They seem to have been really prevalent in the 80s and 90s, but over time we actually see that the trend is really quite stable,” Turanovic says.

"HIPAA doesn't end upon someone's death or incarceration."

Turnaovic is counting mass shootings by sifting through media reports and documents from the FBI. She’s found more than 800 cases so far. The AmmoLand article, which claims all mass shooters in the past 20 years have one thing in common, lists just 39 cases—some of which aren’t mass shootings at all. And Turanovic questions how the article’s author collected their data.

“In my data collection efforts we’re relying on publically available accessible information and so to the extent that if we were to code for that in our data it would be an anecdotal report. So it would be something in a casefile that was unsealed or it would be in a news report—something from a friend or a mother saying ‘this person had mental health problems and they took a lot of Ritalin.’”

She says a person’s medical history isn’t typically available. Jay Reeve is the CEO of the Apalachee Center, a mental health facility in Tallahssee. He says information about the medicines a person is prescribed is protected by federal rules referred to as HIPAA.

“HIPAA doesn’t end upon someone’s death or incarceration,” Reeve says.

He adds that’s even if someone was able to collect information about what medicines mass shooters had been prescribed, he hasn’t seen any evidence to backup the idea that psychotropic drugs would cause someone to become a mass shooter.

“Yeah, I’m kind of trying to think of what psychotropic medication would turn someone into a serial killer and I can’t think of one. That’s not to rule that out, but I’m pretty confident in saying that’s not something that’s popped up in the research at this point,” Reeve says.

Understanding Cause: Psychotropic Drugs Aren't The Cause Of Mass Shootings.

Neither Are Guns.

Reeve says it is likely true that someone who is willing to commit a mass shooting is not a person with a healthy mind. But he says being mentally ill or taking psychotropic drugs does not mean someone will become a mass shooter. In some ways that’s similar to what Representative Hill says about guns.

“There is no statistical analysis that shows that because you confiscate guns from someone with this so called red flag law—all it is is gun confiscation—there is no study that shows that prevents a mass shooting from taking place,” Hill says

Credit Florida House of Representatives Florida Republican Representative Mike Hill says it's his duty as a lawmaker to protect the constitution. That includes filing legislation to repeal rules he says violate the Second Amendment.

In other words, Hill is saying just because someone has guns does not mean they will commit a mass shooting.

Turanovich says when looking at these issues it’s helpful to understand the statistical concept of cause.

“In terms of causation, that’s different from correlation. Two things can seem to be really correlated. But it doesn’t necessarily mean that one is causing the other. For instance, ice cream sales and homicides are actually correlated. But we’re not saying ice cream causes homicide. Homicides are actually just more frequent in the summer. People are outside of their homes more,” Turanovic says

Turanovic says it’s a similar situation for mass shootings. There are a lot of factors that could be correlated, but researchers haven’t found a cause.

“You know this is human behavior. It’s multifaceted. It’s complex. There are biological factors, familial factors, just your individual factors, neighborhood factors, cultural factors that all come into play to influence how people behave at a point in time,” Turanovich says

Turnanovich says it’s incredibly difficult to predict who is going to become an offender or what would make a person stop offending.

“It’s complicated to predict that kind of stuff, Turanovic says. “And so in terms of causal associations I think that a big trap that policy makers often fall into is trying to find simple solutions to complex problems and trying to identify or boil down really complex human behaviors into one or two factors is typically where we go wrong policy wise.”