In the case of Michael A. Whren and James L. Brown v. United States, 1995, the U.S Supreme Court ruled unanimously that as long as officers have a reasonable cause to believe that a traffic violation occurred, they may stop any vehicle. In this case, plainclothes policemen patrolling a "high drug area" in Washington D.C., observed Whren and Brown waiting at an intersection for an unusually long time before turning without signaling and speeding off at an unreasonable speed which led them to pull over their Pathfinder truck. The police then approached the vehicle where they saw two large plastic bags of what appeared to be crack cocaine in Whren's hands leading to their arrest on federal drug charges. The defendants argued that using traffic violations as pretext for drug investigations violates Fourth Amendment protection against unreasonable searches but Justice Antonin Scalia writing for the court held that subjective intentions play no role in ordinary probable-cause Fourth Amendment analysis.

In the dissenting opinion for Whren and Brown v. United States, Justice Stevens argued that the majority's decision to allow police officers broad discretion in stopping vehicles based on probable cause of a traffic violation could potentially lead to racial profiling. He expressed concern that this ruling would enable law enforcement to use minor traffic infractions as a pretext for investigating other potential criminal activities without any reasonable suspicion or evidence. This, he believed, violated the Fourth Amendment’s protection against unreasonable searches and seizures by allowing arbitrary invasions of individual privacy rights based solely on an officer's subjective motivations rather than objective evidence of wrongdoing. Furthermore, he contended that such unchecked discretionary power undermines public trust in law enforcement agencies and exacerbates existing racial disparities within the criminal justice system.