ON MOTION FOR REHEARING
GUITTARD, Chief Justice.In its motion for rehearing, the board asserts that our holding is contrary to the decision of the Supreme Court of Texas in Firemen’s and Policemen’s Civil Service Commission v. Hamman, 404 S.W.2d 308 (Tex.1966), in which the participation of a member of the commission in the investigation was held not to disqualify him from sitting with other members at the hearing at which the officer was suspended. The court does not state whether the investigating commissioner also testified at the hearing, but the opinion of the court of civil appeals shows that he did. Firemen’s and Policemen’s Civil Service Commission v. *253Hamman, 393 S.W.2d 406, 407 (Tex.Civ.App.-Beaumont 1965), aff’d 404 S.W.2d 308 (Tex.1966). Neither opinion indicates what his testimony was, and, since the supreme court discusses his participation in the investigation and in the decision, but does not even mention his testimony, we gather that it was not regarded as crucial to the commission’s decision. Neither court mentions the question of risk of bias, later adopted as the test of a denial of due process in Withrow v. Larkin, 421 U.S. 35, 47, 95 S.Ct. 1456, 1464, 43 L.Ed.2d 712 (1975).
We do not hold that in every case in which a member of an administrative tribunal participates in an investigation and also appears as a witness before it, all members of the tribunal are necessarily disqualified. Neither do we hold that decisions of such a tribunal cannot properly be based on the testimony of its own investigative employees, especially where the agency has organized itself internally to minimize the risk of bias, as was the case in Withrow. Id. at 54, n. 20, 95 S.Ct. at 1468, n. 20. In Hamman, the Supreme Court of Texas expressly recognized that in some circumstances a combination of investigatory and adjudicatory functions may constitute a denial of due process of law. 404 S.W.2d at 312. We hold only that the peculiar circumstances of this case establish an intolerable risk of bias, and therefore, a denial of due process.
The Board argues that since two members of the board are the only witnesses available to support the complaint against appellant and the board is the only tribunal available to hear it, we should apply the “rule of necessity,” which is that disqualification of the members of an administrative tribunal will not be permitted to destroy the only agency with power to take action in the case. It cites Brinkley v. Hassig, 83 F.2d 351 (10th Cir.1936), and other cases. In Brinkley it appears that the unprofessional actions which prompted the complaint against the physician in question were so public and so notorious that they were well known to all members of the licensing board before the complaint was made. The court observed that if the power of the board could not be exercised because of the prejudice of its members, then any physician who commits an offense so grave that it shocks every right-thinking person would have an irrevocable license to practice if he could only get the news of his offense to the board in advance. Id. at 357.
No such situation is shown here. If appellant was engaging in unprofessional conduct, the board had staff investigators who could have observed it and served as witnesses without any necessity for members of the board to step aside as adjudicators and take upon themselves the role of investigators and witnesses. We adhere to the view that this irregular procedure was a denial of due process under the circumstances.
Motion overruled.
AKIN, J., dissents.