In the 1905 case of Pearson v. Williams, the U.S. Supreme Court ruled on an immigration issue involving a British subject who had been living in New York for over two years before being ordered to be deported under an act that was passed after his arrival. The court held that Congress could not retroactively apply laws regarding deportation and thus, Mr. Williams could not be deported based on this law as it did not exist at the time of his entry into the United States. This decision established important precedent concerning ex post facto application of laws and affirmed immigrants' rights against retroactive legislation.

In the dissenting opinion for Pearson v. Williams, Justice Harlan argued that the majority's decision to deport a British subject who had lived in America since infancy was unjust and contrary to established principles of international law. He contended that the man should be considered an American citizen due to his long residence and lack of any criminal record or disloyalty towards America. Furthermore, he pointed out that under English common law, which forms part of U.S legal tradition, a person born on foreign soil but raised from infancy in England would be considered an English subject. Therefore, by this logic, it is inconsistent and unfair not to apply similar rules within American jurisdiction. The justice also expressed concern about potential diplomatic issues arising from such decisions as they could lead other nations into questioning whether their citizens residing in America are safe from arbitrary deportation orders.