How Do We Determine the Voluntariness of a Confession ?
"Under Evidence Code sections 402 and 405, the voluntariness of a confession is a 'preliminary fact' that a trial judge must determine before the confession may be submitted to the jury. " (People v. Hoyos (2007) 41 Cal.4th 872, 897, overruled on other grounds in People v. Black (2014) 58 Cal.4th 912, 920.)
"If a preliminary fact is also a fact in issue in the action: (1) The jury shall not be informed of the court's determination as to the existence or nonexistence of the preliminary fact." (Evid. Code, 405, subd. (b), (b)(1).)
As the United States Supreme Court has explained, while the voluntariness of a confession is a legal issue for the trial court, the separate factual question of the confession's reliability is an issue for the jury. (Crane v. Kentucky (1986) 476 U.S. 683, 690; People v. Ramos (2004) 121 Cal.App.4th 1194, 1205-1206.)
In Crane, the petitioner (a 16-year-old) wanted to testify regarding the physical and psychological environment in which his confession was obtained in order to argue that his confession was not credible. (Crane, supra, 476 U.S. at p. 684.)
The Supreme Court found that "blanket exclusion of the proffered testimony about the circumstances of petitioner's confession deprived him of a fair trial." (Id. at 690.)
"Stripped of the power to describe to the jury the circumstances that prompted his confession, the defendant is effectively disabled from answering the one question every rational juror needs answered: If the defendant is innocent, why did he previously admit his guilt" Accordingly, . . . and entirely independent of any question of voluntariness, a defendant's case may stand or fall on his ability to convince the jury that the manner in which the confession was obtained casts doubt on its credibility." (Id. at p. 689).
The opportunity to be heard "would be an empty one if the State were permitted to exclude competent, reliable evidence bearing on the credibility of a confession when such evidence is central to the defendant's claim of innocence. In the absence of any valid state justification, exclusion of this kind of exculpatory evidence deprives a defendant of the basic right to have the prosecutor's case encounter and 'survive the crucible of meaningful adversarial testing.' " (Id. at pp. 690-691 90 L.Ed.2d at p. 645.)