Ex parte Tom Tong was a United States Supreme Court case that dealt with the issue of whether a Chinese immigrant was entitled to a writ of habeas corpus. The case arose when Tom Tong, a Chinese immigrant, was arrested and detained by the United States Marshal in San Francisco. Tong had been arrested for violating the Chinese Exclusion Act, which prohibited Chinese immigrants from entering the United States. Tong filed a petition for a writ of habeas corpus, arguing that he was unlawfully detained and should be released. The Supreme Court held that Tong was not entitled to a writ of habeas corpus because he was not a citizen of the United States and therefore did not have the right to challenge his detention. The Court reasoned that the Chinese Exclusion Act was a valid exercise of Congress’s power to regulate immigration and that Tong’s detention was lawful. The Court’s decision in Ex parte Tom Tong established that Chinese immigrants were not entitled to the same rights as citizens of the United States. The decision was later overturned by the Supreme Court in the case of United States v. Wong Kim Ark, which held that all persons born in the United States, regardless of race or nationality, were citizens of the United States.

In Ex Parte Tom Tong, the Supreme Court was asked to consider whether a Chinese man who had been denied entry into the United States should be allowed to remain in the country. The majority opinion held that he could not stay because of his status as an alien and lack of legal residence. Justice Field dissented from this decision, arguing that it violated both due process and equal protection under the law. He argued that since Tong had already established himself in California prior to being denied entry, he should have been given a hearing before being removed from the country. Furthermore, Field argued that denying him admission based solely on his race or nationality was unconstitutional discrimination against aliens which Congress did not intend when passing immigration laws. Ultimately, despite Justice Field's dissent, Tom Tong was deported back to China without ever having received a hearing or any other form of judicial review for his case.