The United States Immigrant Inspector's job was to conduct face to face interviews with all immigrants in a crucial proceeding known as immigrant inspection. Every single foreigner that entered the Port of New York was questioned - either on board ship or at Ellis Island itself. Sitting at a high "rostrum desk" in Ellis Island's Registry Room, the inspector consulted the official list of a ship's passengers called a Manifest of Alien Passengers.
In questioning the newcomer, the Immigrant Inspector verified the immigrant's answers given by checking them against what had been originally recorded on the ship's passenger manifest at the port of departure. Because he was only allowed to admit persons who were "clearly and beyond a doubt entitled to enter the United States," he had to be absolutely certain the person he was examining was not a member of one of the classes of persons barred from entering the country under the various US immigration laws, such as contract laborers, polygamists, paupers, convicted criminals, anarchists or anyone "likely to become a public charge."
National Park Service, Statue of Liberty NM
Harvey Snider (1870-1937) U.S. Immigrant Inspector