Car searches and probable cause
Sometimes I think that the easy answer to the question, "How does the 4th Amendment apply to car searches?" is, "It doesn't."
That's a bit cycnical, but you'd be excused from coming to that conclusion after reading the 8th District's decision last week in State v. Beavers. Beavers had decided to spend the night with his girlfriend at the house she shared with her brother and mother. Unfortunately, the brother apparently was a drug dealer, and when the police executed a search warrant, they found drug paraphernalia throughout the house, and some marijuana under the bed Beavers and the sister were sleeping in. They found Beavers' car parked illegally outside, and a quick flashlight scan of the interior showed marijuana and some joints lying on the console. The police squad's drug-sniffing dog with the definitely-not-man's-best-friend name of "Boss" alerted to the vehicle. After obtaining Beavers' keys, the cops found ammo in the glove compartment and a gun in the trunk, leading to Beavers' prosecution for having a weapon under disability.
Beavers raised a number of objections to the search, including his arrest inside the house, but the court ignored that and focused on the search of his car. Rightly so; whether Beavers was properly arrested, or even whether his car was illegally parked, was irrelevant -- case law holds that there's no constitutional barrier to the police shining a flashlight into a car, and the question then became what could the officers do after they saw marijuana in the car.
Quite a lot, actually. There's also a bunch of cases which hold that observing marijuana in a vehicle gives probable cause to search the vehicle. That includes the trunk; back in 1982, in US v. Ross, the US Supreme Court held that probable cause to search a vehicle under the automobile exception to the warrant requirement allowed the search to extend to everything that a warrant would have permitted: an officer may search the entire vehicle, and any containers in the vehicle, which could contain the item for which cause exists to search.
Actually, Beavers gives a good demonstration of how screwed up search and seizure law is in this area. Just last year, in State v. Farris, the Ohio Supreme Court held that the officers' detection of the smell of burnt marijuana in a car couldn't justify a search of the vehicle's trunk. (I discussed Farris here.) This, despite the fact that just six years earlier, in State v. Moore, they'd held that the smell of marijuana did give probable cause to search the vehicle, and the Farris court makes no effort to explain why Ross and Moore should shouldn't be read to allow a search of the trunk in that situation. In fact, Farris relies primarily for that on an Ohio Supreme Court decision which holds that a search of the trunk can't be conducted pursuant to an arrest, but that's not the same thing. A search incident to an arrest of an automobile driver or passenger is limited to the interior of the automobile, but searches incident to arrest have always been much more limited: you can't search the trunk of a car under those circumstances for the same reason that you can't search the upstairs bedroom simply because you arrest someone in his kitchen.
The Beavers court distinguished Farris on the basis that the case there involved the smell of burnt marijuana, while here it involved the actual discovery of the contraband. Arguably, the court overlooked the question of whether finding "contraband" which does not even constitute an arrestable offense -- possession of less than 100 grams of marijuana is a minor misdemeanor -- creates probable cause to search the car. Then again, the court noted that an inventory search of the vehicle would have discovered the weapon, and search of the trunk is permissible for an inventory search.
I'm not the most enthusiastic supporter of expanded rights to searches, as you might have gathered, but I can understand the frustration of police officers with all this. I make a fair part of my living studying this stuff, and it can take a while to sort all of it out. How cops do it in the couple of seconds or minutes they have to make a decision is beyond me.