That's kind of circular, though. Granting a warrant based solely on an officer's claim that he smelled pot is no different from the cop being able to do it on his own without a warrant. In both cases, the only evidence is the cop's claim to have smelled pot.
Again, I'm not advocating for "I smelled pot" to be an insufficient justification in general. But if I were a judge, and someone was trying to suppress evidence of a search that didn't find pot, I'd want to know how often this cop has stopped drivers in the past for smelling pot, but not found any pot in the car.
@Maj. Bill Martin I am more interested in the claim recorded before the fact of the search. Not perfect I know - But certainly more substantiated than an officer's claim after the fact. Witnessed by another officer, all the more so, though collusion is still possible.
Personally, I would allow no search of my property without a warrant, which I think is the only proper recourse. But the state has written a law providing for an unconstitutional search, so far upheld. So there it is.
As to the smell of pot without finding pot, that can happen all the time - pot makes an interior reek just as much as cigarettes do... I can get in a car and immediately know whether the owner is a pot user, with the first whiff. The smell is a sure indicator that the owner is involved with pot, and that it is smoked regularly in the vehicle. Where to go from there is up for grabs, but that much is certainly true.