In Euziere v. United States, the petitioner was convicted for refusing to answer questions before a grand jury regarding possible violations of federal narcotics laws. The Supreme Court held that the petitioner's conviction could not stand because he had been denied his right to counsel during his appearance before the grand jury. The court noted that although there is no absolute right to have counsel present during grand jury proceedings, in this case, where complex legal issues were involved and potential self-incrimination was at stake, denying access to an attorney violated due process rights under the Fifth Amendment of U.S Constitution.

In the dissenting opinion for Euziere v. United States, it was argued that the majority's decision to uphold a conviction based on evidence obtained through an allegedly illegal search and seizure violated the Fourth Amendment rights of the defendant. The dissenting justices contended that by allowing such evidence to be used in court, they were effectively endorsing unlawful police conduct and undermining constitutional protections against unreasonable searches and seizures. They further suggested that this ruling could set a dangerous precedent, potentially leading to more widespread abuses of power by law enforcement officials in future cases. It was their belief that any evidence obtained unlawfully should not be admissible in court under any circumstances as it fundamentally contradicts principles of justice and fairness enshrined within American legal tradition.