Mapp v. Ohio: The Origin of The Exclusionary Rule In State Courts

The “Throw Back Thursday” Blog: Examining classic cases that continue to be relevant.


In my first “Throw-Back-Thursday” blog issue, I take the reader back to the ultimate classic in criminal law, to what is probably the most earth-shattering opinion in criminal law decided in the twentieth century, which is still applicable and going strong in the criminal courts today throughout the United States.  If there is any one case that has had more influence and generated more change in the way criminal cases are handled in state courts throughout the United States, it must be Mapp v. Ohio.  I am sure that we are all familiar with the holding in general, but here is a refresher on the case in this week’s Throw-Back-Thursday Blog.

Mapp v. Ohio

U.S. Supreme Court

367 U.S. 643

Decided on June 19, 1961

Issue: Whether evidence obtained by searches and seizures that are in violation of the United States Constitution is inadmissible at state trials and whether the “exclusionary rule,” which applies to federal courts, should also apply in state courts.

Holding: The Supreme Court held that the exclusionary rule, which forbids the use of unconstitutionally obtained evidence in federal courts, should also apply to evidence in state courts as due process right and that unconstitutionally obtained evidence should be suppressed in state criminal trials.

Citing Boyd v. United States, 116 U.S. 616 (1886), the Supreme Court found that   the Fourth and Fifth Amendments of the Constitution are applicable to all invasions by the government to the sanctity of a man’s home and the privacies of life. It is not the breaking of his doors, and the rummaging of his drawers, that constitutes the essence of the offense; but it is the invasion if his indefeasible right of personals security, personal liberty and private property. Breaking into a house and opening boxes and drawers are circumstances of aggravation; but any forcible and compulsory extortion of a man’s own testimony or of his private papers to be used as evidence to convict him of crime or to forfeit his goods, is within the condemnation of those Amendments.

Facts: In 1957, police forcibly entered appellant Dollree Mapp’s home and conducted a warrantless search after receiving a tip that evidence of a bombing might be there. While no evidence related to the bombing was found, in the course of the search, police discovered sexually explicit material (“lewd and lascivious books”), which was prohibited in Ohio at the time.

Mapp did not give the police permission to enter her residence, stating that they did not have a warrant. Eventually, the police forcefully entered the house and claimed to have a valid search warrant, though they did not allow Mapp to inspect it. After Mapp grabbed the warrant, despite officers’ attempt to prevent her from doing so, a struggle ensued and an officer grabbed Mapp and twisted her arm while she pleaded with him to stop. The police arrested Mapp and the events that followed would lead to the illegal seizure of pornographic materials and a guilty conviction, yet no valid search warrant was ever produced.


Analysis: A landmark U.S. Supreme Court decision written by Justice Tom Clark, Mapp v. Ohio (1961) strengthened Fourth Amendment protections by making it illegal for evidence obtained without a valid warrant and in violation of the Fourth Amendment to be used in criminal prosecutions in state courts. At this time, the “exclusionary rule,” which made illegally obtained evidence inadmissible in federal prosecutions, was already in effect. However, prior to Mapp v. Ohio, no such protection existed for defendants prosecuted in state courts throughout the country.  Interestingly, the Supreme Court declined to address the question of whether the Ohio ban on “obscene” material violated Mapp’s First Amendment right to freedom of expression. Instead, the Court focused its entire opinion on the Fourth Amendment (searches and seizures) and Fourteenth Amendment (due process rights) issues.

Examination of Wolf v. People of State of Colorado

Twelve years prior to the Mapp case, the Supreme Court heard Wolf v. People of State of Colorado, 338 U.S. 69 S.Ct. (1949), where the Court decided to extend protections of due process to unconstitutionally unreasonable state or federal searches, emphasizing the importance of the security of citizens’ privacy. Nevertheless, that Court concluded that states still have the right to present unconstitutionally obtained evidence in court.

As the Mapp Court noted, since the Wolf decision, several states had adopted the exclusionary rule, including California who reasoned that other state remedies had “failed to secure compliance with the constitutional provision.” The Mapp Court rejected the Wolf ruling’s failure to enforce the exclusionary rule in state courts, deeming it contrary to the essential due process rights it upheld within its own opinion.

Due Process Application to the Fourth Amendment and the Decision of the Century

Following its rejection of the Wolf panel’s refusal to recognize the exclusionary rule as a state due process right, the Supreme Court historically held that evidence obtained by searches and seizures in violation of the U.S. Constitution should also be inadmissible in state court, noting that “the exclusionary rule is an essential part of both the Fourth and Fourteenth Amendments.” The Court opined that this decision was a logical and necessary next step, given the Fourth Amendment’s right of privacy had already “been declared enforceable against the States through the Due Process Clause of the Fourteenth Amendment.”

Reminding the reader that the Supreme Court has enforced against states the due process right to not be convicted when a coerced confession is involved, it questioned why the same should not apply here when police have similarly ignored the rules of law in the course of an illegal search. While the Court reasoned its new ruling was the logical prescription following prior cases, it also noted “there is no war between the Constitution and common sense.”

Mapp v. Ohio’s Presence and Relevance in the United States Today


 Now dating more than half of a century ago, Mapp v. Ohio is one of the most significant decisions in U.S. Supreme Court history. It has tightened the reins on unconstitutional searches and has barred the admission of evidence from such searches in state courts. Mapp hearings now take place in courts across the United States to determine whether evidence should be suppressed due to an unlawful search or seizure.