In the 1907 case Liu Hop Fong v. United States, the Supreme Court ruled on a matter concerning immigration law and policy. The plaintiff, Liu Hop Fong, was a Chinese immigrant who had been denied entry into the U.S., despite having previously lived in San Francisco for many years and fathering children born there. He claimed that his rights under an 1894 treaty between China and America were violated when he was refused re-entry after visiting China. However, the court upheld his exclusion based on provisions of an act passed by Congress in 1888 which prohibited all Chinese laborers from entering or re-entering America unless they could provide evidence of their previous residence through white witnesses only - something Mr. Liu couldn't do as he only had Chinese witnesses to testify for him.

In the dissenting opinion for Liu Hop Fong v. United States, Justice Harlan argued that the majority's decision was a misinterpretation of the Chinese Exclusion Act and its amendments. He believed that these laws were designed to prevent new immigration from China but did not intend to exclude Chinese individuals who had already established legal residence in America before their enactment. In his view, Liu Hop Fong’s departure from America should not have invalidated his right to return as he had previously been lawfully admitted into the country and maintained an ongoing domicile there. Furthermore, he contended that any ambiguities in immigration legislation should be resolved in favor of immigrants' rights due to potential severe consequences like deportation or prolonged detention which could result from restrictive interpretations.