As rumors, innuendo, and 4chan-fueled hoaxes swirl around the latest mass shooting to horrify the country, a new culprit has been put forward to explain the last days of Las Vegas shooter Stephen Paddock: Maybe it was the drugs. As you well know by now, the 64-year-old allegedly took aim at some 22,000 people attending a country music concert from the 32nd floor of the Mandalay Bay hotel on Sunday night, killing close to 60 people and injuring more than 500, before shooting himself.
On Wednesday, the Las Vegas Review-Journal reported that Paddock was prescribed the anti-anxiety drug diazepam, better known by its brand name, Valium, in June. He was prescribed 50 tablets of 10 milligrams each. Mel Pohl, chief medical officer of the Las Vegas Recovery Center, told the Review-Journal that the drug, despite being a sedative, has been associated with aggressive—even violent—behavior, particularly in people with underlying aggression problems.
Other news outlets and social media gadflies, like Dilbert creator and conspiracy theorist Scott Adams, have settled on Paddock's suspected mental illness and medication use as a possible explanation for his shooting spree. Is that actually a reasonable theory?
Diazepam is part of a class of drugs known as benzodiazepines, or benzos, which have been around since the 1960s. They've long been used to treat everything from alcohol withdrawal to insomnia, since they help depress brain activity. But though they can be effective in the short term, doctors have become much more wary of them since their heyday in the 1970s. That's because when taken for too long, benzos can become habit-forming and cause a long list of adverse effects, including an increased risk of suicide. People who abuse benzos also tend to mix them with other drugs, like opioids and alcohol, to ramp up the sleepy buzz they cause. It's these drug combinations that are most responsible for the nearly 9,000 overdose deaths involving benzos seen annually.
Crucially, we also know people can experience "paradoxical" effects when taking benzos. Instead of feeling sedated, they feel excited, paranoid, and yes, even aggressive. Research has also suggested a possible link between violent behaviors and using certain kinds of medications, including benzos. A 2015 study by Finnish researchers, for instance, found that Finns convicted of murders from 1995 to 2011 were noticeably more likely to be taking benzos, even after controlling for other risk factors.
But there are plenty of reasons to doubt that the above has anything to do with Paddock's actions, says Yupei Hu, a psychiatrist at the Center for Anxiety and Related Disorders at Boston University.
"When people say aggressive behavior can be related to Valium, they're usually talking about very, very young people or the elderly. In them, it can cause something called delirium—basically someone becomes disinhibited and confused, which then might make them aggressive," Hu tells Tonic. "[But in Paddock's] situation, it seems this was well-planned. I'd be very reserved about the chances that this was related to his use of it. He probably more used it to calm himself down."
According to law enforcement reports, Paddock brought 23 guns to his hotel suite, 12 of which he modified into fully automatic assault rifles using devices called bump stocks. He also set up cameras he may have used to monitor people trying to enter his room, which he had rented out days before. And he may have even scouted other hotel locations in other cities like Boston before settling on the Mandalay Bay. Paddock, reportedly a multimillionaire who gambled frequently, is also believed to have bought a ticket for his live-in girlfriend, Marilou Danley, to leave the country and visit the Philippines about a week prior to the shooting.
"I don't think [Valium] causes people to make wrong decisions, to hurt other people," Hu says. "This shooting is very different. It was intentional."
In the 2015 Finnish study, benzos weren't the type of drug most associated with homicidal urges. That distinction belonged to opioid and non-opioid painkillers (meanwhile, antidepressant use, also often blamed in the wake of mass killings, wasn't associated with a substantial increased risk at all).
Though Hu isn't able to comment on Paddock's case specifically, she says mental illness shouldn't be seen as a guiding reason for mass shootings. People with certain mental illnesses may be more likely to harm themselves, or be victimized by others, but the odds of them committing violent crimes aren't appreciably higher than so-called normal people; rather, the odds are similar, she says.
Benzos can be plenty dangerous, especially if abused, but as many have pointed out, they don't turn users into someone capable of killing more than 50 people in ten minutes' time.
Correction 10/5/17: This story has been updated with the correct spelling of Yupei Hu. We regret the error.
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