Whether the Fifth Amendment and Miranda require suppression of physical evidence derived from a suspect's voluntary but unwarned custodial statement.
Holding
No. Physical fruits of voluntary statements obtained without Miranda warnings are admissible, even though the unwarned statement itself may not be introduced in the prosecution's case in chief.
Reasoning
The Self-Incrimination Clause protects a person from being compelled to be a witness against himself in a criminal case. Its central concern is compelled testimonial evidence, not the introduction of nontestimonial physical evidence. A gun is physical evidence, and admitting it does not itself make the defendant a witness against himself.
Miranda supplies a prophylactic safeguard against the risk that custodial interrogation will produce compelled testimony. In the absence of warnings, Miranda generally presumes coercion and bars the unwarned statement from the prosecution's case in chief. But the rule extends beyond the Fifth Amendment's literal protection, so any further extension must be necessary to protect the actual privilege against compelled self-incrimination.
The Court's precedents already show that Miranda's exclusion rule is not unlimited. Voluntary statements taken without warnings may be used for impeachment, and an unwarned statement does not automatically taint later evidence or statements. Excluding the statement itself is a complete and sufficient remedy for the relevant Miranda violation when the statement was voluntary.
Dickerson's description of Miranda as a constitutional rule did not change this conclusion. Dickerson reaffirmed Miranda's core rule that unwarned statements may not be used in the prosecution's case in chief, while also relying on decisions that had limited Miranda's consequences. It did not hold that every failure to warn is itself a completed Fifth Amendment violation requiring suppression of all derivative evidence.