In the 1890 Supreme Court case In re Delgado, a man named Manuel Delgado was arrested in New York and ordered to be extradited to Puerto Rico on charges of forgery. The issue at hand was whether or not the extradition laws applied between U.S. states and territories like Puerto Rico. Delgado's lawyers argued that since Puerto Rico is an unincorporated territory of the United States, it should not be treated as a foreign country for purposes of extradition law. The Supreme Court ruled against Delgado, stating that even though Puerto Rico is part of the United States, it still has its own separate legal system under federal supervision. Therefore, it can request extradition from other parts of the United States just like any other jurisdiction with its own criminal laws. This decision reinforced that while territories are part of America they also have distinct legal systems which must cooperate with each other through processes such as extradition.

The dissenting opinion in the case of In re Delgado, 1890, argued that the majority's decision to uphold a law prohibiting Chinese immigrants from landing in Puerto Rico without consent from Spanish authorities was an overreach of federal power. The dissent contended that this ruling violated principles of international law and individual rights. They believed it was inappropriate for U.S courts to enforce foreign laws on American soil or against individuals seeking asylum or refuge within its borders. Furthermore, they disagreed with the majority's interpretation of treaty obligations between Spain and China as justification for enforcing such restrictions. The dissenters held that these treaties did not give either country authority to regulate immigration unilaterally but rather required mutual agreement on any changes made regarding immigration policies.