The United States brought an appeal against Rosa Pacheco and others, devisees under the last will and testament of Juan A. Sanchez de Pacheco, deceased. The case concerned a dispute over title to certain lands in California that were granted by Mexico to one Jose Antonio Estudillo in 1842 prior to the Mexican-American War. The Supreme Court held that when Mexico ceded California to the United States, it did not divest itself of its right or power over these lands; rather, it transferred them with all their rights and privileges intact. Furthermore, since there was no evidence that Estudillo had ever conveyed his interest in these lands before his death or otherwise divested himself of ownership thereof during his lifetime, they remained vested in him at the time he died intestate without issue; thus passing by descent according to Spanish law as part of his estate upon which letters of administration were issued after due notice given for creditors' claims against said estate. Therefore, since Rosa Pacheco was appointed administrator on behalf of her father's estate (which included these disputed lands), she had legal authority over them until such time as they could be lawfully disposed off through sale or other means authorized by law.

In the United States v. Rosa Pacheco and Others, Devisees Under the Last Will and Testament of Juan A. Sanchez de Pacheco, Deceased, a dissenting opinion was issued by Justice Field in which he argued that the majority's decision to uphold an act of Congress granting title to certain lands in California was unconstitutional. He believed that this act violated Article IV Section 3 of the Constitution because it allowed for private property rights to be taken without due process or just compensation as required under the Fifth Amendment. Furthermore, he argued that since there had been no treaty with Mexico ceding these lands prior to their acquisition by Congress they were not legally part of U.S territory at all and thus could not be subject to any laws passed by Congress regarding them. In conclusion, Justice Field asserted his belief that this case should have been decided differently than it had been so as not violate either constitutional provisions or international law principles concerning land ownership rights between nations