Ziang Sung Wan v. United States

Mr. Justice Brandéis

delivered the opinion of the Court.

On January 31, 1919, the police department of the District of Columbia learned that three Chinamen, the inmates of a house in Washington occupied by the Chinese Educational Mission, had been murdered. They were known to have been alive late in the evening of January 29. Police officers were told by Li, a student, that, earlier on the same evening, he had seen at the Mission a resident of New York City named Wan. Acting under instructions of the superintendent of police, two detectives started immediately for New York, taking Li with them.…