Mark Manicki (plaintiff), a police officer in his one-year probationary period for the City of Ottawa, Illinois (City) (defendant), witnessed a fight between two other officers. The fight was started by an officer favored by the police chief, Brian Zeilmann (defendant), who told Manicki to inform criminal investigators that both officers were equally at fault. When Manicki refused to change his statement, Zeilmann wrote to the City’s Board of Fire and Police Commissioners (Board), stating that Manicki had failed to perform adequately during his probationary period and should be fired. The Board fired Manicki without a hearing. Manicki sued the Board and Zeilmann in Illinois state court, contending that the Board violated his right to due process by failing to hold a hearing in light of Zeilmann’s retaliatory letter. The Illinois court decided in favor of the Board and Zeilmann. Manicki then filed a lawsuit in a federal district court against Zeilmann and the City, alleging that Zeilmann’s retaliatory conduct violated Manicki’s First Amendment rights. The district court dismissed Manicki’s case on the basis of res judicata. Manicki appealed.