US v. Mason: Mason was driving on Interstate 20 in Georgia when he was pulled over due to having illegally tinted windows. Prior to writing Mason a warning, the officer talked with him and his passenger, who told different stories about where they had been and why. The officer, suspecting they were involved in drug activity (I-20 is a know drug corridor and Atlanta, the direction from which Mason was travelling, a source city) radioed for a K9 unit to assist him. When the K9 unit arrived, the dog alerted, first on the outside of the car and then by leaping inside an open window and further alerting. A search of the trunk revealed 10 kilograms of cocaine. Mason was charged and convicted, following an unsuccessful motion to suppress, of trafficking in more than five kilograms of cocaine and was sentenced to a mandatory sentence of life in prison.
On appeal, Mason challenged both the denial of his motion to suppress and his life sentence. As to the motion to suppress, Mason argued that the officer lacked reasonable suspicion to prolong the stop past the issuance of the warning ticket and that the dog's entry into the car violated the Fourth Amendment. On the first argument, the Fourth Circuit disagreed, holding that the officer had sufficient evidence to conclude that criminal activity was afoot. Although several of the facts were consistent with innocent travel, when taken as a whole the facts rose to the level of reasonable suspicion. As to the dog, the court noted that once the dog alerted to the presence of drugs outside the car there was probable cause to search the vehicle, so the dog's entry did not violate the Fourth Amendment. The court also held, addressing an argument that appeared only during oral argument, that the officer's questions prior to issuing the warning did not unduly lengthen the stop. As to Mason's sentence, the court held that he had not carried his burden of showing that two prior state convictions were obtained without counsel, even if the statute of limitations in 21 USC 851(e) did not prevent review of the issue.
Judge Gregory dissented on the search issue. He argued that the officer did not have reasonable suspicion to extend the traffic stop, after "supplementing and clarifying some key facts . . . that are omitted by the majority."