938, 949-50 (10th Cir.2008). Even assuming without deciding we were free to revisit the governing standard of review, we question whether de novo review would be appropriate or make any difference in this case. Even when the constitutional fact doctrine applies, credibility determinations remain subject to clear error review, see Harte-Hanks Commc'ns, Inc. v. Connaughton, 491 U.S. 657, 688, 109 S.Ct. 2678, 105 L.Ed.2d 562 (1989), and a sincerity finding is in the end "almost exclusively a credibility assessment,” Kay v. Bemis, 500 F.3d 1214, 1219 (10th Cir.2007). In those few instances where the Supreme Court has mandated de novo review of facts involving a litigant’s state of mind, the inquiry has usually involved some purely legal question. See Bose, 466 U.S. at 511, 104 S.Ct. 1949 (<HOLDING>); Miller v. Fenton, 474 U.S. 104, 116-17, 106
holding that on appeal an appellate court does not have the right to weigh the evidence and decide the issue on the basis of its weight the courts duty goes no further than to determine whether the record contains any evidence tending to support the finding holding that the court evaluating a claim of qualified immunity must first determine whether the plaintiff states a claim of a constitutional violation at all and then must determine whether the claimed right was clearly established before proceeding to the qualified immunity question holding that an appellate court is not required to search the appellate record with no guidance from the briefing party to determine if the record supports the partys argument holding appellate court must when evaluating actual malice in libel case independently determine whether the evidence in the record  is of the convincing clarity required to strip the utterance of first amendment protection recognizing that appellate court is in same position as trial court to assess evidence when all of the proof is contained in the record by deposition