“lists have been compiled of mass and random killers and their pot backgrounds.”
Many articles have been written over the years that everyone of these were on, or just recently quit prescription psychotropic drugs and this is the major suspect in all of them. Not the Pot.
This reality has been discussed at length here many times before.
A additional issue. Even though....
.... yes, much overlap in those samples of the population. ;)
One hopes that comprehensive drug screen will be performed, with the complete results released to the public.
One also hopes that the prescribed drug history as well as the mental history of the fungal perp will be obtained and that info released, as well.
I need lots of info before I put an opinion together (other than that the perp is the lowest of the low, that one is simple.)