Wis. Stat. § 908.04
Adequate medical evidence of probable psychological trauma is required to support an unavailability finding based on trauma, absent an emotional breakdown on the witness stand. State v. Sorenson, 152 Wis. 2d 471, 449 N.W.2d 280 (Ct. App. 1989). The state must show by a preponderance of the evidence that the declarant's absence is due to the defendant's misconduct under sub. (2). State v. Frambs, 157 Wis. 2d 700, 460 N.W.2d 811 (Ct. App. 1990). When testimonial statements are at issue, the only indicium of reliability sufficient to satisfy constitutional demands is confrontation. "Testimonial statements" applies at a minimum to prior testimony at a preliminary hearing, before a grand jury, or at a former trial and to police interrogations. Crawford v. Washington, 541 U.S. 36, 124 S. Ct. 1354, 158 L. Ed. 2d 177 (2004). A finding of unavailability of a witness due to mental illness, made on the basis of a confused and stale record, deprived the defendant of the right to confront witnesses, but the error was harmless. Burns v. Clusen, (1984). Hearsay and the Confrontation Clause. Biskupic. Wis. Law. May 2004.