During his term as Attorney General, he issued a set of guidelines (in 1976) to limit the activities of the FBI. These guidelines required the FBI to show evidence of a crime before using secret police techniques like wiretaps or entering someone's home without warning. These guidelines were replaced by new ones issued in 1983 by Ronald Reagan's Attorney General, William French Smith. He urged President Ford to appoint Robert Bork, who was his former student and Solicitor General, or fellow Chicagoan John Paul Stevens to the United States Supreme Court, and Ford followed his advice. Levi later testified in support of Bork at his confirmation hearing. Serving under him, in various high staff positions, were such people as Rudolph Giuliani, Robert Bork, Antonin Scalia, Rex E. Lee, and Arthur Raymond Randolph.