Miranda v. Arizona (1966) is one of the most famous and most controversial decisions of the United States Supreme Court. In 1963, a young woman from Arizona was driven into the desert and was raped. The police convicted and arrested Miranda. Miranda was interrogated for several hours without understanding his constitutional rights, including the benefit of counsel. The only exhibit at the state trial was his confession. Miranda then took this to the Supreme Court, challenging this on the grounds of the Fifth Amendment.
The court presented one major question: Does the police practice of interrogating individuals without notifying them of their right to counsel and their protection against self-incrimination violate the Fifth Amendment? The court answered, yes, it does violate the Fifth Amendment. So, in this controversial decision (5-4), the Supreme Court reversed Miranda's conviction.
The Court reasoned that the prosecutors could not use statements of defendants which came from interrogation, unless they demonstrated the use of procedural safeguards "effective to secure the privilege against self-incrimination." In addition, the Supreme Court stated that "the modern practice of in-custody interrogation is psychologically rather than physically oriented" and that "the blood of the accused is not the only hallmark of an unconstitutional inquisition." The Court then required the usage of police warnings to suspects, which warn them that they have the right to remain silent, the right to have counsel present during interrogations, and other things. This Due Process guarantee requires that a suspect "must be warned prior to any questioning that he has the right to remain silent, that anything he says can be used against him in a court of law, that he has the right to the presence of an attorney, and that if he cannot afford an attorney one will be appointed for him prior to any questioning if he so desires. Opportunity to exercise these rights must be afforded to him throughout the interrogation." Miranda was tried again, and was then found guilty.
Many consequences stemmed from this controversial decision. First of all, suspects must be read thier Miranda rights, which wasn't a requirement before. Suspects of crimes, now will have a fair chance of defending themselves, and will be aware of their constitutional and due process rights when being arrested or being convicted.
Sources:http://oyez.nwu.edu/cases/cases.cgi and notes from Government class.