I don't understand what you aren't getting. The dispatch got a call at 11 pm that night. The guy shot was smoking weed that night. Are you saying because we don't know the exact time he was shot means the story is BS?
Nah, he's saying that there's no proof that the shooter himself was high, since it only mentions the victim of the article having smoked.
Edit :
I'll answer the same way I answered before. Take your average driver and give them a beer to drink. Most if not all would have no ill effects in motor skills. Now take the same person and let them smoke a joint. Their motor skills would be affected. Do I have "Scientific" proof? No, I've just been around enough people in my life who were stoned and I myself used to get stoned about 20 years ago.
I'm not sure how this relates to my post, since I certainly haven't encouraged anyone to get high and drive! If you want to elaborate a little, I'd be happy to give my viewpoint on what you're getting at.