In the United States v. Sokolow case of 1988, the Supreme Court ruled that law enforcement officers can use a combination of factors to determine reasonable suspicion for a search and seizure under the Fourth Amendment. The defendant, Andrew Sokolow, was stopped at Honolulu Airport by Drug Enforcement Administration (DEA) agents based on several suspicious behaviors: he paid $2100 for two airplane tickets from a roll of $20 bills; his trip was only 48 hours long even though it took him 20 hours to fly round-trip from Miami; he seemed nervous during his journey; and he did not check any luggage. Although none of these actions were illegal individually, collectively they aroused suspicion among DEA agents who then seized cocaine found in Sokolow's carry-on bag. In an opinion written by Justice Byron White, the court upheld that while individual acts may be innocent in isolation, "taken together they amounted to reasonable suspicion," thereby justifying law enforcement's action.

In the dissenting opinion for United States v. Sokolow, Justice Marshall argued that the majority's decision to uphold Sokolow's conviction based on a Drug Enforcement Administration (DEA) agent’s profile of drug couriers was flawed. He contended that this approach allowed law enforcement officers too much discretion in determining what constitutes suspicious behavior and could potentially lead to racial or ethnic profiling. Furthermore, he believed it violated Fourth Amendment protections against unreasonable searches and seizures by lowering the standard of reasonable suspicion required for police stops and detentions. In his view, none of Sokolow's actions individually constituted illegal activity nor did they collectively suggest criminal intent when viewed objectively without bias or preconceived notions about drug traffickers' behaviors.