The search incident to arrest exception to the Fourth Amendment's warrant requirement permits officers to search a suspect upon making an arrest. It is the most commonly invoked justification for unconsented-to searches; indeed, incident searches far exceed searches conducted with a warrant. This seemingly straightforward exception has wilted in recent years as courts have done away with the prerequisite of an arrest, permitting incident searches so long as there is pre-search probable cause to arrest. The result has been to grant authority to search any person engaged in the most minor of offenses—e.g., speeding, littering, jaywalking—even absent an arrest, injecting routine warrantless searches into this most common form of police-citizen encounter.

This Article takes aim at pre-arrest incident searches and diagnoses two doctrinal missteps courts make in permitting them. The first is ignoring that Fourth Amendment intrusions must be judged at their inception, a maxim that dictates any post-search arrest is irrelevant to the constitutional calculus (except as evidence of some pre-search fact). The second is that they interpret Whren v. United States—in which the Supreme Court held that a seizure supported by probable cause was valid without regard to whether it was pretextual—as an evidentiary bar to considering officer intentions in Fourth Amendment inquiries. That is wrong too: Whren is not an evidentiary bar at all. While officer intentions are irrelevant to certain objective questions (like probable cause), they matter when discerning whether a custodial arrest is under way. Once these two mistakes are corrected, a straightforward rule emerges: incident searches are permitted only if there is a custodial arrest (be it completed or in-progress) at a search's inception.

Correcting the two missteps above has broad implications. Reinvigorating the principle that intrusions must be judged at their inception has reverberations in all manner of Fourth Amendment analyses. Likewise, treating Whren as a broad evidentiary bar to considering officer intentions is a pervasive yet ultimately mistaken approach. This Article offers a course correction on an issue that has deeply divided appellate courts and is likely to soon receive Supreme Court consideration.