Mich. Comp. Laws § 38.28
Should a member cease to be an employee before attaining age 60 years, or after attaining such age but before becoming eligible for a retirement allowance, for any reason except his retirement or death, or should a member be granted military leave as prescribed by the rules of the civil service commission, he shall be paid his accumulated contributions standing to his credit in the employees' savings fund, as he shall demand in writing upon forms furnished by the retirement board, subject to section 30. Any person who has withdrawn his accumulated contributions, as provided for in this section, and who again becomes a member, may restore to the employees' savings fund the amount previously withdrawn by him, together with regular interest from the date of withdrawal to the date of repayment. If the constitutional court administrator becomes a member of the judges' retirement system established by Act No. 198 of the Public Acts of 1951, as amended, being sections 38.801 to 38.830 of the Compiled Laws of 1948, he shall thereupon cease to be a member of this retirement system, regardless of his age, and his accumulated contributions standing to his credit in the employees' savings fund shall be returned to him.
MCL 38.28