Overview
Miranda v. Arizona, 384 U.S. 436 (1966), was a landmark decision of the U.S. Supreme Court in which the Court ruled that the Fifth Amendment to the U.S. Constitution restricts prosecutors from using a person's statements made in response to interrogation in police custody as evidence at their trial unless they can show that the person was informed of the right to consult with an attorney before and during questioning, and of the right against self-incrimination before police questioning, and that the defendant not only understood these rights but also voluntarily waived them.
Miranda was viewed by many as a radical change in American criminal law, since the Fifth Amendment was traditionally understood only to protect Americans against formal types of compulsion to confess, such as threats of contempt of court. It has had a significant impact on law enforcement in the United States, by making what became known as the Miranda warning part of routine police procedure to ensure that suspects were informed of their rights. The concept of "Miranda warnings" quickly caught on across American law enforcement agencies, who came to call the practice "Mirandizing".
Pursuant to the U.S. Supreme Court decision Berghuis v. Thompkins (2010), criminal suspects who are aware of their right to silence and to an attorney but choose not to "unambiguously" invoke them, may find any subsequent voluntary statements treated as an implied waiver of their rights, and used as or as part of evidence. At least one scholar has argued that Thompkins "fully undermined" Miranda.
Background
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