Kevin Groesch, Greg Shaffer, and Scott Allin are all white males, were all police officers in the Springfield, Illinois Police Department, all voluntarily resigned from the department, all sought reemployment with the department, and all were ultimately rehired between 1989 and 1996 as entry-level officers pursuant to City policy. Donald Schluter, on the other hand, is African-American. He also was a Springfield police officer who sought reinstatement after a voluntary resignation. He was rehired in 2000 -- but he was given a retroactive leave of absence and he returned to the force with full credit for his prior years of service. The City policy had not changed but the City Council enacted a special ordinance allowing the exception. The police union challenged the ordinance in state court but it was upheld. The City ignored the white officers' request to be credited with their prior years of service. A state court dismissed, on statute of limitations grounds, the officers’ lawsuit alleging disparate treatment under the Illinois Constitution. The officers then filed race discrimination claims under Title VII in federal court in 2004. Judge Scott (C.D. Ill.) denied the City's motions for summary judgment in late 2006, relying on the "paycheck accrual" rule, under which each department paycheck amounted to a separate discriminatory act. Five months later, however, the Supreme Court decided Ledbetter and rejected the paycheck accrual rule. The district court reversed course and granted the City's motion. The court also ruled that the officers' § 1983 claims were barred by res judicata because they could have been brought in the state court action. The officers appeal.

In their opinion, Judges Bauer, Wood, and Hamilton affirmed in part, reversed in part, and remanded. The Court first noted that Congress enacted the Lilly Ledbetter Fair Pay Act of 2009 during the pendency of the appeal. In effect, the Act reinstated the paycheck accrual rule and also made the reinstatement retroactive to any claim pending on the day of the Supreme Court's decision or later. The City attempted to avoid application of the Act or distinguish the case -- but to no avail. The Court reversed the district court with respect to the Title VII claims relating to the time period after the state court dismissal. Next, although the Act only directly applies to Title VII actions, the Court concluded that the paycheck accrual rule applied to pay discrimination claims under § 1983, as well. Finally, the Court considered the impact of the earlier state court decision. Under Illinois law, res judicata requires a final judgment, an identity of causes of action, and an identity of parties. The district court correctly concluded that res judicata bars recovery for claims that arose before the date of the final judgment. But each individual paycheck after that final judgment supports a separate cause of action and triggers a new statute of limitations. They therefore do not share an identity of causes of action and are not barred by res judicata. The Court emphasized that the state court had never ruled on the merits, therefore not implicating collateral estoppel or issue preclusion.