Myra Clark Gaines v. Manuel J. Lizardi et al was a landmark case in the United States Supreme Court. The case involved a dispute over the ownership of a large estate in New Orleans, Louisiana. Myra Clark Gaines, the plaintiff, claimed that she was the rightful owner of the estate, while the defendants, Manuel J. Lizardi and others, argued that they had a valid title to the property. The Supreme Court ultimately sided with Gaines, ruling that she was the rightful owner of the estate. The Court held that the defendants had failed to prove their title to the property, and that Gaines had a valid claim to the estate. The Court also held that the defendants had failed to prove that they had a valid title to the property, and that Gaines had a valid claim to the estate. The decision in this case was significant because it established the principle that a person's title to property is not necessarily dependent on the validity of the title held by another person. This ruling has been cited in numerous cases since then, and has been used to protect the rights of property owners.

Myra Clark Gaines was a resident of Louisiana who brought suit against Manuel J. Lizardi and others, claiming that she had been illegally deprived of her inheritance rights by the defendants. The Supreme Court held that the case should be dismissed because it involved a dispute over title to land in Louisiana, which was subject to state law rather than federal law. Justice Field dissented from this decision on the grounds that there were questions of federal jurisdiction at issue in this case as well as issues concerning interstate commerce and foreign relations between France and Spain (the two countries whose laws governed ownership of property in Louisiana). He argued that these matters fell within Congress' power under Article III, Section 2, Clause 1 of the Constitution; thus they could not be decided solely by state courts but must instead come before a court with original jurisdiction such as the U.S. Supreme Court itself or one established by Congress for such purpose.