In People v. Guenther, 740 P.2d 971 (Colo. 1987), the court decided that Colorado's similar immunity statute authorized a trial court to dismiss a criminal prosecution at the pretrial stage and did not merely create an affirmative defense for adjudication at trial. Id. at 976. The court further determined that a defendant raising the immunity would have the burden of establishing the factual prerequisites to the immunity claim by a preponderance of the evidence. Id. at 980. The court imposed the same burden of proof as it would in motions for postconviction relief or motions to suppress. Id.