This article analyzes the Supreme Court’s decision in Borough of Duryea v. Guarnieri, which held that in order for a petition, grievance or litigation by a public employee to be protected against retaliation under the Petition Clause of the First Amendment of the United States Constitution it must satisfy the public concern test applicable in retaliation cases alleging a violation of the Speech Clause. The decision was issued in the midst of a renewed contemporary debate over public sector collective bargaining and other statutory rights in public employment. The article analyzes the decision in the context of American public sector labor history, which includes a legacy of explicit prohibitions on public employees petitioning for improved working conditions and limitations on their right to freely associate for mutual aid and protection. In reaching its decision, the Court overlooked the centrality of petitioning in public sector labor relations. The article closely examines the factual and the state legal background of the case to highlight the importance of statutory and contractual protections in public employment, and the pitfalls when those protections are abandoned in favor of constitutional litigation. Finally, the article examines the overlooked question of what enforceable constitutional rights remain for public employees if or when statutory protections and rights are eliminated or substantially curtailed.