The fraudulent medium Ronald Edwin confessed he had duped his séance sitters and revealed the fraudulent methods he had used in his book Clock Without Hands (1955). The psychical researcher Tony Cornell investigated the mediumship of Alec Harris in 1955. During the séance "spirit" materializations emerged from a cabinet and walked around the room. Cornell wrote that a stomach rumble, nicotine smelling breath and a pulse gave it away that all the spirit figures were in fact Harris and that he had dressed up as each one behind the cabinet.
In 1880 the American stage mentalist Washington Irving Bishop published a book revealing how mediums would use secret codes as the trick for their clairvoyant readings. The Seybert Commission was a group of faculty at the University of Pennsylvania who in 1884–1887 exposed fraudulent mediums such as Pierre L. O. A. Keeler and Henry Slade. The Fox sisters confessed to fraud in 1888. Margaret Fox revealed that she and her sister had produced the "spirit" rappings by cracking their toe joints.
In 2013 Rose Marks and members of her family were convicted of fraud for a series of crimes spanning 20 years entailing between $20 and $45 million. They told vulnerable clients that to solve their problems they had to give the purported psychics money and valuables. Marks and family promised to return the cash and goods after "cleansing" them. Prosecutors established they had no intent to return the property. https://drive.google.com/file/d/1ZxhJSNFx0QgywAEljeOS_TUw5e9jgeq8/view?usp=sharing
Michael Shermer criticized mediums in Scientific American, saying, "mediums are unethical and dangerous: they prey on the emotions of the grieving. As grief counselors know, death is best faced head-on as a part of life." Shermer wrote that the human urge to seek connections between events that may form patterns meaningful for survival is a function of natural evolution, and called the alleged ability of mediums to talk to the dead "a well-known illusion of a meaningful pattern."
No doubt a great importance in the paranormal field is the problem of fraud. The field of psychic research and spiritualism has been so notoriously full of charlatans, such as the Fox sisters and Eusapia Palladino–individuals who claim to have special power and gifts but who are actually conjurers who have hoodwinked scientists and the public as well–that we have to be especially cautious about claims made on their behalf. https://drive.google.com/file/d/1jfIdkes6t1TCleih9mebaywuoSViJSRK/view?usp=sharing