[cynwoody]

Valium is a tranquilizer. People don’t go postal from it.

A 2015 Finnish study found that people are 45% more likely to commit murder on benzodiazepines than when clean.

[LouieFisk]

“A 2015 Finnish study found that people are 45% more likely to commit murder on benzodiazepines than when clean.”
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I’d wager that most were coffee drinkers, too. Sorry, but unless you can find specific instances of people on Valium, in specific, going on murder sprees it’s just barking up the wrong tree.
I think it would be more safe, if you’re going down the “mental road”, to say the guy was a longtime psycho and just managed to hide it well from most people.