Walker v. The State Harbor Commissioners is a United States Supreme Court case that was decided in 1873. The case involved a dispute between the plaintiff, Walker, and the defendant, the State Harbor Commissioners, over the ownership of a pier in the harbor of San Francisco. Walker had built the pier in 1867 and had been using it for his business since then. The State Harbor Commissioners had attempted to take possession of the pier in 1871, claiming that it was part of the public harbor and thus belonged to the state. Walker argued that he had a valid claim to the pier, as he had built it and had been using it for his business for four years. The Supreme Court ultimately sided with Walker, ruling that the State Harbor Commissioners had no right to take possession of the pier. The Court held that the pier was not part of the public harbor, and thus the state had no right to take possession of it. The Court also held that Walker had a valid claim to the pier, as he had built it and had been using it for his business for four years. The Court thus ruled in favor of Walker, and the State Harbor Commissioners were not allowed to take possession of the pier.

In Walker v. The State Harbor Commissioners, the Supreme Court was tasked with determining whether a state law that allowed for the condemnation of private property in order to build a public harbor was constitutional. Justice Field dissented from the majority opinion and argued that while it is true that states have broad powers to regulate their own internal affairs, this power does not extend so far as to allow them to take away an individual's right to their property without just compensation. He further argued that if such laws were upheld then individuals would be deprived of one of their most fundamental rights - namely, the right to possess and enjoy what they lawfully acquire - which he believed violated both natural justice and due process under the Fourteenth Amendment.