The Borough of Duryea (in Pennsylvania) fired its police chief. He then filed a complaint with the police union that got him his job back. Later, he filed another complaint that led to changes in some of the demands the borough made of him. Feeling like he was on a roll, the chief next filed a federal lawsuit against the borough. He claimed that they had infringed on his right to petition the government for redress (guaranteed by a less famous part of the First Amendment).
After the lawsuit eventually worked its way through the system, the Supreme Court of the United States decided the matter. The Court held that backlash against a government employee’s petition does not create liability under the First Amendment unless it relates to a matter of public concern.
Now a lower court will decide the case, with the new Supreme Court guideline in mind. Litigation sometimes seems to never end.