The stereotypical private investigators of books, TV and movies don't always show the full spectrum of the work that private investigators do on a day-to-day basis. A real investigator's caseload often includes background investigations, surveillance and skip traces, or searches for missing people. Investigators may also serve legal documents, notifying people of their involvement in legal proceedings. In the United States, this is part of the due process guaranteed in the Fifth and 14th Amendments to the Constitution.