Traditionally confessions have been considered the gold standard of evidence creating an almost irrebuttable proof of the defendant's guilt.This began to change in the 1800's when the U.S. Supreme Court first began to question strong-handed interrogation tactics:
A confession freely and voluntarily made is evidence of the most satisfactory character. But the presumption upon which weight is given; to such evidence -- namely that an innocent man will not imperil his safety or prejudice his interests by an untrue statement, ceases when the confession appears to have been made -- either in consequence of inducements of a temporal nature held out by one in authority, touching the charge preferred, or because of a threat or promise made by, or in the presence of, such person, in reference to such charge.
It wasn't until 1936 that the Supreme Court determined that involuntary confessions were abhorrent to the Due Process Clause of the 14th Amendmement of the U.S. Constitution:.
Coercing the supposed state's criminals into confessions and using such confessions so coerced from them against them in trials has been the curse of all countries. It was the chief inequity, the crowning infamy, of the Star Chamber and the Inquisition, and other similar institutions. The constitution recognized the evils that lay behind these practices, and prohibited them in this country. . . . The duty of maintaining constitutional rights of a person on trial for his life rises above mere rules of procedure, and wherever the court is clearly satisfied that such violations exist, it will refuse to sanction such violations and will apply the corrective.
Confessions which are involuntary may be excluded from evidence unless the defendant opens the door to the admission of the confession. Recent studies have demonstrated that false confessions are a real and ever present threat to fair adjudication of criminal cases.
The exclusion of involuntary evidence is premised on three principals. First, exclusion of involuntary confessions tends to deter police misconduct. Second, a confession should be freely made by a rational person. Finally, confessions obtained with duress are inherently unreliable.
Voluntariness is determined by a factfinder (judge or jury) by examining and taking into consideration the totality of the circumstances.
Factors may include objective factors such as:
- Duration of the interrogation
- Length of pre-trial detention
- Place and conditions of interrogation
- Psychological threats
- Police conduct during interrogation
- Whether force or threat of force was used during interrogation.
Similarly, the factfinder must examine the defendant's subjective state of mind to determine whether given all those factors, the confessions was, in fact, involuntary. In doing so, they should consider the defendant's physical and mental characteristics: age, race, education, history and psychological state of mind during the interrogation.
Deception alone is usually not enough to warrant exclusion of a confession as involuntary. In Frazier v. Cupp , the U.S. Supreme Court upheld the admissibility of a confession when the police falsely told the defendant that his cousin had confessed to the crime. The Court held that deception was just one factor in the voluntariness test and that deception in and of itself was not dispositive.
In certain circumstances, police misconduct may be so egregious that the confession evidence should be excluded without regard for how that conduct affected the defendant.
See Confessions, McNabb-Mallory Rule