Martha Mitchell effect
The Martha Mitchell effect is the name for a false diagnosis, where a medical professional falsely labels a patient's perception of real events as a delusion. Martha Mitchell (1918-1976) was the wife of John Mitchell, United States Attorney General in the Nixon administration.  When she said that White House officials were involved in illegal activities, her claims were attributed to mental illness. In the end, the facts of the Watergate scandal proved her statements to be true. Because of what she had told, Martha Mitchell became known as "The Cassandra of Watergate".