I think you're right. When I've taken Valium (a bendodiazepine) for sleep, I definitely feel less aggressive, downright docile even. I cannot imagine this drug would induce someone to murderous rage.
It might be the case that people with prior uncontrollable rage might have been prescribed some form of calming drug, thus leading to the correlation.
That's what I think. The kind of people who are given such drugs may already have homicidal tendencies. This could be like a study showing that gun owners are more likely than non-gun owners to shoot someone.
Take off the blindfold. You need to review the suicides and mass shootings in which these drugs figure, although the manufacturers and their psychiatrist shills have been managing to suppress the bad news and consequent exposure of conflicting interests of the parties inflicting this epidemic of so-called "psychotropic" chemicals on their gullible audiences, IMHO.
Do the homework, then come back with a verifiable report, OK?
Being finally make aware of this, I have personal knowledge of several people whose lives have been really messed up by this class of antidepressant/antianxiety classed drugs.