Summary
In Whren v. United States, the Supreme Court unanimously held that a traffic stop supported by probable cause does not violate the Fourth Amendment just because officers may have had an additional investigative motive. The decision affirmed an objective Fourth Amendment rule for traffic stops.
Legal Issue
Does a traffic stop violate the Fourth Amendment when officers have probable cause for a traffic violation, but may have had another investigative motive?
Holding
No. A temporary traffic stop is reasonable under the Fourth Amendment when officers have probable cause to believe a traffic law was violated. The officers' subjective motives do not invalidate an objectively justified stop.
Rule of Law
If police have a valid traffic-law reason to stop a car, the stop usually stands under the Fourth Amendment even if the officer was also hoping to investigate something else.
Court Reasoning
Not yet summarized.
Impact for Officers
Whren remains central to traffic-stop litigation, policing policy, racial profiling debates, suppression motions, and training on the difference between constitutional authority and department policy.
What Officers Can Do
Not yet summarized.
What Officers Should Avoid
Not yet summarized.
Common Misunderstanding
Not yet summarized.