57.991.  Effect of benefits on eligibility for benefits in other systems. — 1.  For members of the system prior to December 31, 2023, the benefits provided for by sections 57.949 to 57.997 shall in no way affect any person's eligibility for retirement benefits under the local government employees' retirement system, sections 70.600 to 70.755, or any other local government retirement or pension system, or in any way have the effect of reducing retirement benefits in such systems, or reducing compensation or mileage reimbursement of employees, anything to the contrary notwithstanding.

  2.  Any new members employed under this section, on or after January 1, 2024, shall be subject to the following provisions:

  (1)  A member of another state or local retirement or pension system who begins employment in a position covered by the sheriffs' retirement system shall become a member of the sheriffs' retirement system upon employment.  Any membership in any other state or local retirement or pension system shall cease, except that the member shall be entitled to benefits accrued through December 31, 2023, or the commencement of membership in the sheriffs' retirement system, whichever is later; and

  (2)  Subject to the limitations under sections 57.949 to 57.997, the board shall have the authority to formulate and adopt rules and regulations for the administration of these provisions.