In the case of Harris v. New York, 1970, the U.S Supreme Court ruled that statements obtained in violation of the Miranda rule could be used to impeach a defendant's credibility during cross-examination. The defendant, William Harris was arrested and made incriminating statements before he was read his rights under Miranda v. Arizona (1966). At trial, these statements were not introduced as evidence by prosecution but when Mr. Harris testified differently than his previous statement on stand during defense testimony; prosecution used those initial remarks for impeachment purposes - to challenge his credibility. The court held that while such illegally obtained evidence cannot be directly used against a suspect at trial due to Fifth Amendment protections against self-incrimination; it can still be utilized indirectly for challenging their truthfulness if they choose to testify inconsistently with prior admissions.

In the dissenting opinion for Harris v. New York, Justice William Brennan Jr., joined by Justices Hugo Black and Thurgood Marshall, argued that using a defendant's statements obtained in violation of Miranda rights as impeachment evidence undermines the constitutional privilege against self-incrimination. They contended that this practice would encourage law enforcement to ignore Miranda warnings with impunity, knowing they could still use any resulting statements to impeach defendants who chose to testify. The dissenters also expressed concern about potential abuse of this rule by prosecutors who might deliberately introduce tainted evidence early on in order to "open the door" for its later use during cross-examination. They believed such tactics were fundamentally unfair and inconsistent with principles of due process and justice.