The president and high ranking officials enjoy privileged communications where such communication is not subject to being required to be produced in a court of law if the revelation of the communications would be of a nature which would significant affect the president’s or the officials’ ability to do their jobs property and with effectiveness. While the privilege is broad (and similar in nature to other privileges like the attorney-client privilege), it is not absolute and is not in effect if the communications complained of are criminal in nature.
In summary – the President of the United States as well as other high ranking officials enjoy a “privileged communication” when they discuss important matters in secret. A subpoena to compel the President and others to testify what was said in court will not be effective. It is similar to the privilege enjoyed by attorney-client or doctor-patient privilege. If all of the President’s communications were subject to being revealed in a court of law, the President would not be able to perform his or her job effectively. This special privilege of confidential communications is called the “executive privilege” when it pertains to the President or a high ranking official.