Mapp v. Ohio

Dollree Mapp was convicted of possessing obscene materials after an admittedly illegal police search of her home for a fugitive. She appealed her conviction on the basis of freedom of expression.


All evidence obtained by searches and seizures in violation of U.S. Const. amend. IV is, by that same authority, inadmissible in a state court.

Brief Fact Summary:

All evidence discovered as a result of a search and seizure conducted in violation of the Fourth Amendment of the United States Constitution (“Constitution”) shall be inadmissible in State court proceedings.

Case Commentary:


The Mapp v. Ohio Decision The outcome of this case was a ruling in favor of the appellants based on the fact that conducting a warrantless search of private property was a violation of the Fourth Amendment right to privacy as a “right to be secure against rude invasions of…[private property]…by state officers”. The Court described how the Fourth and Fifth Amendments “apply to…invasions on the part of the government…of a man’s home and the privacies of life”. It countered the state’s argument from the lower court with the note that protections for “the security of person and property” need be “liberally construed”. Adding to that counter-argument, it noted how courts have found that using evidence unconstitutionally gathered during trial denies suspects their constitutional rights. The Court also found that inherent in that “right to be secure against” such invasions to privacy was the exclusion of evidence gathered by way of unconstitutional search and seizure procedures. It outlined how the exclusion of such evidence is required based on the holding in the Weeks case and subsequent cases. It noted that the failure of the court in the state case cited by Ohio to recognize the exclusionary rule alongside protections for the Fourth Amendment right to privacy was the result of an unusual fact pattern. The Court explained how the Due Process Clause allowed for enforcement of the Fourth Amendment right to privacy through such exclusion of evidence. It went on to state that the enforcement of the Fourth Amendment right to privacy via the Due Process Clause is permissible against states as well as against the federal government.