U.S. Customs and Border Protection (CBP) officials (“customs officials”) can set up temporary checkpoints, also known as “roadblocks,” in strategic locations within 100 miles of the U.S. border. The law regarding this kind of checkpoint can be murky. For example, some courts have held that detentions at these points require reasonable suspicion, but they’ve also indicated that reasonable suspicion in this setting is easily satisfied. (For related reading, see the discussion of reasonable suspicion in When can roving border patrols stop and question you?)
Courts will treat some temporary checkpoints similarly to permanent checkpoints when it comes to search-and-seizure issues. Indeed, how a court will treat a “temporary” checkpoint may depend in part on how “permanent” it actually is.
Stops at temporary checkpoints must be momentary. But if a customs official develops probable cause regarding an immigration or non-immigration-related offense during the brief stop, the official can extend the detention for further investigation.
(For more on this area of law, including information on the importance of legal consultation, see our article on Search and Seizure at and Around the U.S. Border. And for information on the potentially complicating factor of state (rather than federal) law, see Does state law factor into border searches?)