Is well settled that "a person cannot be committed to a mental hospital solely on the basis of these medical certificates of examination; competent medical or psychiatric testimony is necessary." Porter v. State, 703 S.W.2d 840, 843 (Tex. App.--Fort Worth 1986, no writ) (citing Munoz v. State, 569 S.W.2d 642, 644 (Tex. Civ. App.--Corpus Christi 1978, no writ)). A court may base its findings on medical certificates alone only when the proposed patient has waived his right to cross-examine witnesses. See In re D.F.R., 945 S.W.2d 210, 213 (Tex. App.--San Antonio 1997, no writ). It follows that, unless a proposed patient waives the right to cross-examine witnesses, the court must hear competent expert testimony and may not make its findings solely from the medical certificates. See id. Indeed, if there has been no waiver, and expert testimony is required, then the medical certificates are not even required to be introduced into evidence during the course of a commitment proceeding. See K.L.M. v. State, 735 S.W.2d 324, 325 (Tex. App.--Fort Worth 1987, no writ).