Well, according to Montana Code Annotated 2009, it's not:
2-3-203. Meetings of public agencies and certain associations of public agencies to be open to public -- exceptions. (1) All meetings of public or governmental bodies, boards, bureaus, commissions, agencies of the state, or any political subdivision of the state or organizations or agencies supported in whole or in part by public funds or expending public funds, including the supreme court, must be open to the public. [emphasis added].