Contrast with keying a car and being labeled a terrorist. By scratching a cybertruck, you become an enemy of the state—something a republican school shooter could never dream of.

Tbf, it's a common conspiracy theory that all of them (or at least a significant portion) are on SSRIs. I think it comes from a mix of

A. Some of them were iirc, but I'm not sure who. It's also possible it just was used as an excuse by a parent, or kid who didn't die in their shooting.

B. Simply just the fast part of the commercials that says "if you are experiencing suicidal or homicidal ideation while taking lexapro, talk to your doctor immediately.." and then people being people, that gets extrapolated into "the shooters are on SSRIs and this is why it happens." People are searching for answers as to the underlying causes, on both sides of the "gun bad" and "gun good" debate, the same way some focus on "if we got rid of guns" those that know "well my gun doesn't make me want to shoot up schools so it isn't the guns" but have never taken SSRIs might be more apt to blame the thing they're less familiar with, for instance.

C. Afaik, it hasn't actually been studied very well and actually could play a role in at least some of the incidents, but we don't "know." First of all, I think HIPAA presents some challenges in studying this, as I think even prisoners have the right to medical privacy. And on top of that I wouldn't be surprised to learn Big Pharma's lobbyists are hard at work making sure this is not well studied to the best of their ability, it's kinda just their MO to the degree I'd be surprised if they weren't doing that. Our pharma lobby is just as bad as tobacco about that, if not worse.

Personally, I'd actually like to see this possible link or lack thereof studied in depth myself, if for no other reason than to quell the conspiracy theory, or if a link is found then maybe we can do something about that, I think only good can come from at least just studying it.

The few studies that I have seen actually suggest there may actually be a link, but I don't know exactly how rigorous those were or if it's enough to indicate causation rather than simply correlation, and it's not specific to active shooters but simply "violent crime" (of which shootings are obviously one, but it could be "increased risk of simple assault, but not murder" without narrowing it down, who knows.

https://pmc.ncbi.nlm.nih.gov/articles/PMC4570770/

With age and sex stratification, there was a significant association between SSRIs and violent crime convictions for males aged 15 to 24 y (HR = 1.40, 95% CI 1.13–1.73, p = 0.002) and females aged 15 to 24 y (HR = 1.75, 95% CI 1.08–2.84, p = 0.023). However, there were no significant associations in those aged 25 y or older.

Seems to suggest to me that at the ages these (typically male) shooters usually are, there actually may be a significant enough percentage to suggest a possible causation? I'd still like to see it studied further though, especially if it can be a study specifically regarding active shooter incidents, and also I'd like to know if "was taking them and stopped" plays a role over "is taking them currently" or vice versa. I think it's at least worth a look, especially considering this study itself concludes:

The increased risk we found in young people needs validation in other studies.