42 CFR §412.262

1. (a)Grounds for disqualification. An MGCRB member may not participate in any decision in a case in which he or she may be prejudiced or partial with respect to a party or has any other interest in the case.
2. (b)Request for disqualification. If a party believes that an MGCRB member should not participate in a decision, the party submits the objection in writing to the MGCRB at its earliest opportunity, explaining the grounds for the request. CMS may also submit such a suggestion to the MGCRB.
3. (c)Consideration by the MGCRB member. The MGCRB member will consider the objection and, at his or her discretion, either will proceed or withdraw.
4. (d)Consideration by the MGCRB If the member does not withdraw, a party may petition the MGCRB for withdrawal and the MGCRB will consider the objection and rule on whether the member may participate in the decision before it decides the case.