What exactly are you correlating with? Last I checked there were dozens of murders in the US every single day. Are you correlating with all of those killers? Or just the ones that get media attention and kill unrelated people? I wonder how many of these murderers had tried/done marijuana recently, maybe its the pot that makes them do it. IIRC, jeffrey dahmer was a big pothead.
I think its is likely that in our modern culture, people with mental issues that are prone to commit these types of acts will be put on drugs before they commit the acts. More so than it is the drugs causing them to commit these acts.
I don't think
causing is the right word. Seems to me that many of these drugs make the connection to reality more brittle, making it somewhat more likely for a psychopathic break to occur. That they maybe stabilize someone's day to day perception of the world, but (failing to deal with the underlying issues driving the psychosis) the dissonance will build up pressure and contribute to a larger psychopathic break in the future. Without the underlying psychopathy there would not be a break to trigger in the first place, medicine or no. So I think it comes down to "what came first, the chicken or the egg?"
And no, I am talking specifically about the sensation-seekers, not every murder. Shoot up a schoolyard or snipe 12 people in a town, or some bizarre serial killer. The ones specifically driven by fundamental mental defect. I believe there are many more mentally defective people than there are those who are drugged; and if SSRI's did not contribute in some way to the prevalence of these sensation crimes, then more of them should have appeared by now that have not been taking this specific class of psychotropic drug.
Sure, it is far more likely that they are being drugged nowadays than 50 years ago, but there are still PLENTY of undrugged psychopaths, so these undrugged psychopaths should, reasonably, carry their fair share of the bizarro-murder stats. They don't. There are only a handful of conclusions that can be drawn from that. "Suicide and violent ideations" is a known SSRI side effect.
My understanding is an SSRI can prevent a hundred 'tiny' psychopathic breaks in a year, but if the underlying psychosis is left untreated it can also lead to a gigantic psychopathic break after a couple years. Which would explain why all but 1 or 2 of these sensation murderers in the last 25 years were on some kind of SSRI drug. They used a drug to 'kick the can down the road' until it blew up into...something awful.