The defendant confessed to committing armed robbery. The confession was included at trial. The defendant denied making the confession voluntarily. The state law provided that a challenged confession could be admitted into evidence if, at a hearing outside the presence of the jury, the judge found it voluntary by a preponderance of the evidence.
Whether the standard of proof for voluntariness of confessions is a preponderance of the evidence?
Yes. Proof of the voluntariness of a confession by a preponderance of the evidence is constitutionally adequate.
When the government seeks to use a confession challenged as involuntary, the defendant is entitled to a reliable and clear-cut determination that the confession was in fact voluntarily rendered. The Court held that this is accomplished by requiring the government to prove at least by a preponderance of the evidence that the confession was voluntary. The exclusion of unreliable confessions is not the purpose of a voluntariness hearing. The sole issue in such a hearing is whether a confession was coerced.
404 U.S. 477, 92 S. Ct. 619 (1972)