What is the impact of absolute witness immunity on testimony at trial?

In contrast, as discussed above, the policy considerations applicable to adversarial pretrial proceedings, such as those held in this case, are identical to the policy considerations relevant to testimony at a trial on the merits. In both settings, the risk that false testimony will go undetected is minimized by submitting the testimony to "the crucible of the judicial process so that the factfinder may consider it, after cross-examination, together with the other evidence in the case to determine where the truth lies." Imbler v. Pachtman, 424 U.S. 409, 440, 96 S.Ct. 984, 999, 47 L.Ed.2d 128 (1976) (White, J., concurring in judgment), quoted in Briscoe, 460 U.S. at 334, 103 S.Ct. at 1115. In adversarial pretrial proceedings as well as at trial, absolute witness immunity is essential if the truth-seeking function of the proceeding is to be fully served.