Whether the agents had probable cause, before stopping and searching Brinegar's automobile, to believe that he was unlawfully transporting liquor into Oklahoma.
Holding
Yes. The facts known to the agents before the stop supplied probable cause for the warrantless search of Brinegar's moving automobile.
Reasoning
Carroll v. United States controlled. Like the officers in Carroll, the agents here recognized both a driver and a vehicle associated through recent personal observation with illicit liquor activity. In both cases, the known liquor operator was traveling on a highway from a likely source of liquor toward a likely unlawful market. Those material similarities made the cases indistinguishable for Fourth Amendment purposes.
Malsed's knowledge did not rest merely on reputation or hearsay. He had personally seen Brinegar loading quantities of liquor in Joplin that were greater than normal personal use, had previously arrested him for unlawful liquor transportation, recognized him and his car, and saw him traveling west in Oklahoma shortly after the Missouri line. Those facts supported a reasonable inference that Brinegar was again transporting liquor unlawfully.
Joplin was a convenient legal source of liquor, while Oklahoma prohibited liquor importation without a permit and was a likely illegal market. Brinegar was traveling from Joplin toward Vinita, his Oklahoma home, only a few miles after crossing the state line. The legality of buying liquor in Missouri did not defeat probable cause to believe that Brinegar was illegally bringing it into Oklahoma.
The Court did not need to rely on Brinegar's acceleration or flight after he passed the officers. The officers already had enough information when they recognized him, his car, the apparent load, and his route to form probable cause. His later admission therefore was not needed to validate the search.