Mont. Code Ann. § 19-1-302

The governor shall designate the department director, who shall direct the administrator to conduct and supervise a referendum. The referendum must be conducted in accordance with the requirements of section 218(d)(3) of the Social Security Act, 42 U.S.C. 418(d)(3), on the question of whether service in positions covered by a retirement system established by the state or by a political subdivision thereof should be excluded from or included under this chapter.