In the 1986 case Colorado v. Spring, the United States Supreme Court ruled that a suspect's ignorance of an impending charge does not invalidate their Miranda rights waiver and subsequent confession. The defendant, Robert Spring, was arrested on weapons charges but during his interrogation confessed to a murder he wasn't initially suspected of committing. He argued that because he hadn't been informed about potential murder charges before waiving his Miranda rights (the right to remain silent and have legal counsel present), his confession should be inadmissible in court. However, the Supreme Court disagreed with this argument by a 7-2 vote margin stating that full knowledge of all possible subjects of questioning is not required for a valid waiver; it only requires "knowing and intelligent relinquishment or abandonment" of known rights.

In the dissenting opinion for Colorado v. Spring, Justice Brennan, joined by Justices Marshall and Blackmun, argued that the majority's decision was a significant departure from established precedent on Fifth Amendment rights. They contended that an individual must be fully aware of their constitutional rights before they can truly waive them voluntarily. In this case, the defendant was not informed about potential murder charges when he waived his Miranda rights; thus, according to the dissenting justices, his waiver could not have been made knowingly or intelligently as required by law. The minority also disagreed with the majority's interpretation of "interrogation," arguing it should encompass any situation where police know their actions are likely to elicit incriminating responses from suspects - even if questions aren't directly related to a crime under investigation at that moment.