Whether Fulminante's confession to FBI informant Anthony Sarivola was coerced and therefore inadmissible under the Due Process Clause.
Holding
Yes. A five-Justice majority concluded that the confession was coerced because Fulminante confessed in response to a credible threat of prison violence and Sarivola's offer of protection.
Reasoning
Voluntariness is ultimately a federal legal question, although the Court gives substantial respect to state-court factual findings. The governing inquiry is the totality of the circumstances: whether the defendant's will was overborne rather than whether a promise was merely a but-for cause of the confession.
The Arizona Supreme Court permissibly found that Fulminante, rumored to be a child murderer, faced a credible danger of physical harm from other prisoners. Sarivola knew of the rough treatment and offered protection only if Fulminante told him about the killing.
Actual violence by a government agent is unnecessary. A credible threat of violence, including psychological coercion, can overcome a suspect's will. Because Fulminante confessed in the context of an offer to protect him from feared inmate violence, the Court accepted that his confession was coerced.