Pennsylvania v. Muniz

Background

A man stopped for suspected drunk driving failed roadside sobriety tests, admitted drinking, and was arrested. At the police booking center he was videotaped and asked routine biographical questions, a memory question about his sixth birthday, asked to repeat sobriety tests, and offered a breath test. He did not receive Miranda warnings until after the breath test and later admitted driving while intoxicated. The state appellate court reversed his conviction, suppressing the audio from the booking tape; the State appealed to the Supreme Court.

Reasoning

The Court analyzed which statements are "testimonial" (statements that convey facts or the speaker’s mental state) versus non‑testimonial physical evidence. It held that slurred speech and physical performance (balance, eye jerking) are nontestimonial physical evidence. But asking the memory question about the date of his sixth birthday required a factual response that could reveal his mental state, and that answer was therefore testimonial and should have been suppressed because no Miranda warnings had been given. The Court also accepted a limited "routine booking" exception for ordinary biographical questions and ruled that most of the spoken comments made while performing sobriety tests and during the breath-test explanation were not the product of custodial interrogation and thus were admissible.

Real world impact

Police may generally record and use routine booking information and footage of physical sobriety tests, but they cannot introduce testimonial answers elicited without Miranda — for example, memory questions that reveal mental confusion. The case is remanded so the lower court can reconsider the conviction and any harmless‑error issues.

Dissents or concurrances

Several Justices disagreed about the scope of the booking exception and about whether more statements should have been suppressed, reflecting split views on Miranda’s reach.