Martha Mitchell effect
In general, what the patient reports is seen as a delusion, because it is thought to be improbable.  People with paranoia think they are being followed. People with a delusion have strange beliefs, that are difficult to explain.  No one believed Martha Mitchell, so she was diagnosed both with paranoia, and said to be delusional. Both paranoia, and delusion are mentall illnesses. So, Martha Mitchell was seen as having the symptoms of a mental illness.