United States v. Dionisio

Background

A federal special grand jury in Illinois was investigating gambling-related crimes and had obtained recorded conversations via court orders. The grand jury subpoenaed about twenty people, including Dionisio, and asked them to read intercepted-transcript passages into a recorder as voice exemplars. Witnesses were told they could have lawyers present but refused, citing Fourth and Fifth Amendment protections. The district court ordered compliance and held some in civil contempt; the Court of Appeals for the Seventh Circuit reversed on Fourth Amendment grounds, prompting the Government to appeal to the Supreme Court.

Reasoning

The Court addressed whether forcing a person to give a voice recording violates the privilege against self-incrimination or the Fourth Amendment’s protection against unreasonable searches and seizures. Relying on earlier cases, the Court held that voice exemplars are identifying physical characteristics, not testimonial communications, so the Fifth Amendment does not bar their compelled production. The Court also explained that a grand jury subpoena to appear is not a Fourth Amendment seizure and that a person has no reasonable expectation of privacy in the sound of his voice, so compelling a voice exemplar is not an unreasonable search or seizure. The Court rejected the idea that calling many witnesses made the procedure unconstitutional and reversed the Court of Appeals.

Real world impact

This decision allows grand juries and investigators to require voice recordings from witnesses for comparison with intercepted tapes. It makes it easier for prosecutors to pursue voice-identification evidence during investigations, and reduces a witness's ability to resist on Fourth or Fifth Amendment grounds.

Dissents or concurrances

Justice Marshall (joined by others in dissent) argued a pre‑showing of reasonableness should be required when subpoenas seek voice or handwriting exemplars, warning about potential intrusions on privacy and burdens on witnesses.