When one voluntarily removes the capacity for rational thought, whatever comes after that must be premeditated. If I have a loaded gun in my possession and I take a recreational drug that causes me to do something stupid, those stupid actions were done with intent, because I wouldn’t have done them if not on that drug—i.e. I (under the influence) chose to do them.
That’s really all there is to it. I can’t even claim something was a accident when I remove my own ability to understand what accidents might yet happen.
Once again, are drunk drivers charged with premeditated murder?
What you are stating is not recognized or supported by any court, and that is really all there is to it.
Furthermore, smoking weed doesn’t remove one’s ability to think or understand.
That being said, one should not smoke weed and then drive or handle guns.
That just plain, old stupidity in action.