United States v. Schlesinger was a United States Supreme Court case that dealt with the issue of whether a federal court had the authority to issue a writ of habeas corpus to a prisoner held in a state prison. The case arose when the petitioner, Schlesinger, was convicted of a crime in a state court and sentenced to a term of imprisonment in a state prison. Schlesinger then filed a petition for a writ of habeas corpus in a federal court, seeking to be released from his state prison sentence. The Supreme Court held that the federal court did not have the authority to issue a writ of habeas corpus to a prisoner held in a state prison. The Court reasoned that the writ of habeas corpus was a remedy that was available only to prisoners held in federal custody, and that the federal court did not have the authority to interfere with the state court's judgment. The Court also noted that the writ of habeas corpus was a remedy that was available only in cases where the prisoner was being held in violation of the Constitution or laws of the United States. In conclusion, the Supreme Court held that the federal court did not have the authority to issue a writ of habeas corpus to a prisoner held in a state prison. The Court reasoned that the writ of habeas corpus was a remedy that was available only to prisoners held in federal custody, and that the federal court did not have the authority to interfere with the state court's judgment.

In United States v. Schlesinger, the Supreme Court was asked to decide whether a defendant could be convicted of an offense that had been committed before Congress passed a law making it illegal. The majority opinion found that the defendant could not be held liable for his actions because there was no existing law prohibiting them at the time they were committed. Justice Field dissented from this decision and argued that if Congress has declared certain conduct to be criminal, then those who have engaged in such conduct should face punishment regardless of when their actions occurred. He reasoned that allowing people to escape liability simply because they acted prior to a statute being enacted would undermine public confidence in laws and encourage individuals to engage in activities knowing full well they will never face any consequences for doing so.