Illinois Statutes Chapter 40. Pensions § 5/9-108. “Employee”, “contributor” or “participant”

(a) Any employee of the county employed in any position in the classified civil service of the county, or in any position under the County Police Merit Board as a deputy sheriff in the County Police Department.

Any such employee employed after January 1, 1968 and before January 1, 1984 shall be entitled only to the benefits provided in Sections 9-147 and 9-156, prior to the earlier of completion of 12 consecutive calendar months of service and January 1, 1984, and no contributions shall be made by him during this period. Upon the completion of said period contributions shall begin and the employee shall become entitled to the benefits of this Article.

Any such employee may elect to make contributions for such period and receive credit therefor under rules prescribed by the board.

Any such employee in service on or after January 1, 1984, regardless of when he became an employee, shall be deemed a participant and contributor to the fund created by this Article and the employee shall be entitled to the benefits of this Article.

(b) Any employee of the county employed in any position not included in the classified civil service of the county whose salary or wage is paid in whole or in part by the county. Any such employee employed after July 1, 1957, and before January 1, 1984, shall be entitled only to the benefits provided in Sections 9-147 and 9-156, prior to the earlier of completion of 12 consecutive calendar months of service and January 1, 1984, and no contributions shall be made by him during this period. Upon the completion of said period contributions shall begin and the employee shall become entitled to the benefits of this Article.

Any such employee may elect to make contributions for such period and receive credit therefor under rules prescribed by the board.

Any such employee in service on or after January 1, 1984, regardless of when he became an employee, shall be deemed a participant and contributor to the fund created by this Article and the employee shall be entitled to the benefits of this Article.

(c) Any county officer elected by vote of the people, including a member of the county board, when such officer elects to become a contributor.

(d) Any person employed by the board.

(e) Employees of a County Department of Public Aid in counties of 3,000,000 or more population who are transferred to State employment by operation of law enacted by the 76th General Assembly and who elect not to become members of the Retirement System established under Article 14 of this Code  1 as of the date they become State employees shall retain their membership in the fund established in this Article 9  2 until the first day of the calendar month next following the date on which they become State employees, at which time they shall become members of the System established under Article 14.

(f) If, by operation of law, a function of a “Governmental Unit”, as such term is defined in the “Retirement Systems Reciprocal Act” in Article 20 of the Illinois Pension Code,  3 is transferred in whole or in part to the county in which this Article is in force and effect, and employees are transferred as a group or class to such county service, such transferred employee shall, if on the day immediately prior to the date of such transfer he was a contributor and participant in the annuity and benefit fund or retirement system in operation in such other “Governmental Unit” for employees of such Unit, immediately upon such transfer be deemed a participant and contributor to the fund created by this Article.