Whenever the combined state and city or the combined state and county service of an employee covered by section 100 of this act shall equal or exceed the minimum years of service required by the several units of government under their respective system to be eligible for nonduty disability retirement allowance or benefit, or, for the dependents of such an employee to be eligible for benefits in the event of the nonduty death of such an employee, the state and the city or the county, shall grant such disability or death allowance or benefit upon the following conditions:
If any retirement system does not provide for a nonduty disability retirement allowance or benefit or for nonduty death benefit, then neither the employee nor his dependents shall receive such allowance or benefit from such retirement system nor shall an employee or his dependents receive any retirement allowance or benefit from more than 1 retirement system covering the same service credit period. The provisions of this section shall not apply to any city or county that does not have a retirement system.
MCL 400.102