Fourth Amendment doctrine has been home to two competing models: the Warrant Model and the Reasonableness Model. The Warrant Model, emphasizing the Amendment’s Warrant Clause, holds that search and arrest via warrant is the preferred method and the default rule, though allowing for exceptions when obtaining a warrant is impracticable. The Reasonableness Model, which stresses the Amendment’s Reasonableness Clause, holds that the Amendment imposes a generalized reasonableness standard on searches and seizures by which the question is not whether dispensing with a warrant is reasonable but whether the search or seizure itself is reasonable. These polar positions have been replicated in the scholarly literature on the history surrounding the ad...