Williamson County Board of Commissioners v. Board of Trustees of the Illinois Municipal Retirement Fund
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The Pension Code allowed elected county board members to participate in the Illinois Municipal Retirement Fund (IMRF) if the participant occupied a position requiring 1000 hours of service annually and the public employee filed an election to participate. A 1968 administrative rule required the governing body of a participating employer to adopt a resolution certifying that the position of elected governing body members required the hourly standard. Williamson County complied with the 1968 rule. The plaintiffs satisfied the original requirements for IMRF participation, electing to participate in 2004, 2008, and 2012. In 2016, Public Act 99-900, amended parts of the Pension Code (40 ILCS 5/7-137.2(a), requiring, for the first time, that all county boards certify within 90 days of each general election that their board members were required to work sufficient hours to meet the hourly standard for participation and that members who participate in IMRF submit monthly timesheets. The Fund issued “Special Memorandum #334” to the authorized IMRF agent in every county, explaining the change: “If the County Board fails to adopt the required IMRF participation resolution within 90 days after an election, the entire Board will become ineligible and IMRF participation will end for those Board members.” The Fund also sent a direct mailing to individual county board members participating in IMRF. Williamson County did not timely adopt the required resolution. The Fund notified the plaintiffs that they were not eligible for continued IMRF participation.
The Illinois Supreme Court found Public Act 99-900 invalid under Illinois Constitution article XIII, section 5. A public employee’s membership in a pension system is an enforceable contractual relationship; continued IMRF participation was protected from unilateral legislative diminishment or impairment when the plaintiffs became IMRF participants and began accruing the service credits.
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