Onetrack.
Im not supporting it,but was just refering to the fact that someone who was legless at a party the day before and goes to work next day with a zero blood alcohol reading is probably more of a chance to stuff up than someone who had a silly weed the day before.
He may have been out of his tree or maybe not.The report should have the level of THC which could shed further light.
If I had half a beer and got killed in a crash how would my family feel if the report said alcohol was involved in the crash.