>>/27862/
It's as simple as understanding Akathisia Induced Impulsivity.
There's a certain enzyme in some people's liver that metabolizes SSRIs differently than the mean. For some, Akathisia can set in at seemingly random times, they eventually snap and most kill themselves. Some, however, go all Bird Box and start taking other people out with them.
Of course, sometimes there are examples wherein all they do is forget what happened for a while. In this case, it's easy to pin something on them because of the overwhelming energy around them and their being unsure of what just happened. Some can be convinced they just murdered a bunch of people, like Nick Cruz, for example, who simply exited the building with a few friends that day in Parkland. You know that time those two men in full combat gear run through a school and (supposedly, at least) murdered a bunch of innocent children during a "shooting drill".