In the case of North Carolina v. Butler, 1978, the U.S. Supreme Court ruled that a defendant's silence after being read their Miranda rights does not necessarily constitute an implicit waiver of those rights. The court held that while it is possible for a person to waive their rights through actions and words, this must be done voluntarily and with full understanding of what they are giving up. In this particular case, Robert F. Butler was arrested on charges related to burglary and larceny in North Carolina but did not explicitly acknowledge his understanding or waiver of his Miranda Rights before making incriminating statements during police interrogation; he merely nodded when asked if he understood them. His conviction was overturned by the Supreme Court because there wasn't clear evidence that he had knowingly waived these rights.

In the dissenting opinion for North Carolina v. Butler, Justice William H. Rehnquist disagreed with the majority's ruling that a defendant can implicitly waive their Miranda rights through actions and statements. He argued that this interpretation was inconsistent with previous Supreme Court decisions which required explicit waivers of constitutional rights to ensure protection against self-incrimination and right to counsel during interrogations. He expressed concern over leaving such an important decision up to law enforcement officers' subjective interpretations of defendants' behavior, potentially leading to abuses or mistakes in determining whether a waiver occurred or not. Furthermore, he believed it would create unnecessary confusion in lower courts about how exactly implicit waivers should be identified and evaluated.