Both the United States Constitution and the Colorado Constitution guarantee defendants in criminal cases the right to confront and cross-examine witnesses. U.S. Const. amend. VI, XIV; Colo. Const. art. II, 16. The United States Supreme Court has recognized that this right is "uniquely threatened" when an accomplice's confession is sought to be introduced against such a defendant without the benefit of cross-examination. Lee v. Illinois, 476 U.S. 530, 541, 106 S. Ct. 2056, 2062, 90 L. Ed. 2d 514, 526 (1986); see also People v. Dement, 661 P.2d 675 (Colo. 1983). In Blecha v. People (Colo. 1992), the supreme court reiterated the factors that should be considered in making the harmless error determination: An appellate court should examine a number of factors, including the importance of the witness' testimony to the prosecution's case, whether the testimony was cumulative, the presence or absence of corroborating or contradictory evidence on the material points of the witness' testimony, the extent of the cross-examination otherwise permitted, and the overall strength of the prosecution's case.