In United States v. Reagan, 713 F. Supp. 2d 724, 732 (E.D. Tenn. 2010), a federal court said:
A police officer observes a patron drink several beers in an establishment in a short period of time. If the police officer then observes the patron leave the establishment, get into a vehicle in the parking lot, and drive off, the officer has probable cause to pursue the vehicle, effect a traffic stop, and arrest the driver for DUI.
The court believed that Cantrell and Cain implied a "per se" or categorical rule under which "DUI is an offense that, by its very nature, might yield physical evidence." Id.
Under this rule, the court was concerned that an officer would have an unqualified reason to lawfully search the passenger compartment of the vehicle without a warrant even though he has absolutely no reason to believe that evidence of DUI is inside--to the contrary, his firsthand observation of the driver drinking several beers gives him a good reason to believe that no evidence of DUI is contained in the vehicle. This result seems completely contrary to Gant's statement that a warrantless search of a vehicle's passenger compartment incident to arrest is lawful when "it is reasonable to believe the vehicle contains evidence of the offense of the arrest." (Id. at 733.)
The court held that the officer must have something more than prior experience of finding alcoholic beverage containers in a DUI arrestee's vehicle to justify a search of the vehicle:
The Court acknowledges that a law enforcement officer's general prior experience is certainly one of the common sense factors to consider when deciding the reasonableness of his belief that evidence of a specific crime is located inside of a vehicle's passenger compartment. But in this case, the Court finds that Ranger Garner's general prior experience alone was not enough to establish a reasonable belief that evidence of DUI was contained within the Defendant's vehicle. (Id. at 733-34.)
The court in dicta suggested what it considered to be additional factors that might justify a search incident to arrest.
Many different facts may provide a law enforcement officer with reason to believe that evidence of DUI is located inside the passenger compartment of a vehicle. Examples include observations of the driver drinking while driving, observations of an open container of alcohol in plain view inside the passenger compartment, statements made by the occupants of the vehicle indicating that an open container is in the passenger compartment, the smell of alcohol emanating from within the passenger compartment, or indications that the driver was traveling from a location such as a recreational area or campground where alcohol is not available unless it is transported in by private vehicle. (Id. at 733 n.7.)