In the case of People of Porto Rico v. Rosaly Y Castillo (1912), the U.S. Supreme Court ruled on a matter concerning double jeopardy laws in Puerto Rico, which had recently become a territory of the United States following the Spanish-American War. The defendant, Rosaly y Castillo, was charged with embezzlement and acquitted by a local court in San Juan but then retried and convicted by an American military tribunal for the same crime. He appealed to the Supreme Court arguing that his second trial violated his Fifth Amendment rights against double jeopardy - being tried twice for the same offense. The Supreme Court upheld Rosaly's conviction stating that because Puerto Rico was not fully incorporated as part of America at that time, its inhabitants were not entitled to all constitutional protections afforded to citizens living within states or incorporated territories; thus making it possible for him to be tried twice without violating any constitutional rights under U.S law.

In the dissenting opinion for the case of People of Porto Rico v. Rosaly Y Castillo, Justice Oliver Wendell Holmes Jr. argued that Puerto Rico should not be considered a foreign country in relation to the United States under U.S tariff laws. He disagreed with the majority's interpretation of Downes v. Bidwell (1901), which had established that territories acquired by the U.S were not automatically part of it for constitutional purposes and thus could have different customs regulations applied to them than states did. Holmes believed this ruling was being misapplied in this case, as he saw no reason why Congress would want to treat goods from Puerto Rico differently than those from any other territory or state within its jurisdiction when it came to tariffs and duties.