Cal. Gov. Code § 54956.86

Notwithstanding any other provision of this chapter, a legislative body of a local agency which provides services pursuant to Section 14087.3 of the Welfare and Institutions Code may hold a closed session to hear a charge or complaint from a member enrolled in its health plan if the member does not wish to have his or her name, medical status, or other information that is protected by federal law publicly disclosed. Prior to holding a closed session pursuant to this section, the legislative body shall inform the member, in writing, of his or her right to have the charge or complaint heard in an open session rather than a closed session.