John Joseph Sirica was a judge for the U.S. District Court for the District of Columbia. He presided over the trial of Watergate burglars and used provisional sentencing to encourage the burglars to provide information about higher-ups before final sentencing. When one defendant, James W. McCord Jr. described a broader scheme of involvement by the Nixon administration, Judge Sirica ordered President Richard Nixon to turn over his tape recordings of his White House conversations.
In the letter below from President Nixon to Judge Sirica, Nixon states he refusal to obey the subpoena and turn over his tapes. Nixon cites the long historical precedent of U.S. Presidents not adhering to court orders, noting that official communications between government department heads and their subordinate officers are "privileged communications."