It’s not spurious.
There are some documented cases of people showing the early warning signs of schizophrenia who go full-on nuts after smoking weed.
Of course one could argue they were headed there anyway. Or perhaps not.
But without controlled experiments it’s unlikely to be known for certain.
Disclosure: I support the legalization of marijuana by any state who so chooses.
As do I, but I'll state it another way: I OPPOSE the federal government mandating what is purely a constitutional state issue. I oppose any state, especially my own, legalizing marijuana.
When the bleedover of societal pathologies from neighboring states affects Teas, I'll expect the federal courts to stay OUT of our vigorous prosecution of it.