Knowles v. Iowa

The Supreme Court called the Iowa Supreme Court’s interpretation of its statute a “search incident to citation,” a derivative of a search incident to arrest. The Supreme Court stated that a search incident to arrest was a valid exception to the Fourth Amendment’s warrant requirement because of the need to disarm the suspect and to preserve evidence for later use at trial.

The Court dismissed the consideration of officer’s safety in allowing a search incident to citation because it did not believe the issuance of a citation is as dangerous as an arrest. The officer will not spend as much time with the defendant while issuing a citation, stress levels are not as great and the outcome is not as uncertain as during an arrest. The Supreme Court also held that the second rationale for a search incident to arrest, to secure evidence for later use, is not logical because it is unlikely the officer will find additional evidence of the traffic violation by searching the automobile.