Lamar, Executor v. Micou, Administratrix was a case heard by the United States Supreme Court in 1885. The case involved a dispute between the executor of a will and the administratrix of the estate of the deceased. The executor, Lamar, argued that the administratrix, Micou, had wrongfully taken possession of certain property that was part of the estate. The Supreme Court held that the executor had the right to the property and that the administratrix had no right to take possession of it. The Court also held that the executor had the right to bring an action for damages against the administratrix for her wrongful possession of the property. The Court further held that the executor was entitled to recover the value of the property from the administratrix. The Court also held that the executor was entitled to recover the costs of the action from the administratrix. The Court's decision was a victory for the executor and a defeat for the administratrix.

In Lamar, Executor v. Micou, Administratrix the Supreme Court was asked to decide whether a Georgia statute allowing for an executor or administrator of a deceased person's estate to bring suit against another party on behalf of the estate was constitutional. The majority opinion held that it did not violate due process and thus upheld the statute in question. However, Justice Field dissented from this decision arguing that such statutes violated both due process and equal protection under the law as they allowed one party (the executor) to sue another without giving them any opportunity to be heard or defend themselves before judgment is passed down by a court. He argued that this type of legislation could lead to arbitrary decisions being made which would ultimately undermine justice in America and should therefore be struck down as unconstitutional.