Today "demonstration of mediumship" is part of the church service at all churches affiliated with the National Spiritualist Association of Churches (NSAC) and the Spiritualists' National Union (SNU). Demonstration links to NSAC's Declaration of Principal #9. "We affirm that the precepts of Prophecy and Healing are Divine attributes proven through Mediumship."
In 1970 two psychical researchers investigated the direct-voice medium Leslie Flint and found that all the "spirit" voices in his séance sounded exactly like himself and attributed his mediumship to "second-rate ventriloquism".[173] The medium Arthur Ford died leaving specific instructions that all of his files should be burned. In 1971 after his death, psychical researchers discovered his files but instead of burning them they were examined and discovered to be filled with obituaries, newspaper articles and other information, which enabled Ford to research his séance sitters backgrounds.[174]
In March 2017, medium Thomas John was targeted in a sting operation and caught doing a hot reading. The sting was planned and implemented by skeptical activist Susan Gerbic and mentalist Mark Edward. The unmarried couple attended John's show using aliases, and were "read" as a married couple Susanna and Mark Wilson by John. During the entire reading, John failed to determine the actual identities of Gerbic and Edward, or that they were being deceptive during his reading. All personal information he gave them matched what was on their falsified Facebook accounts, rather than being about their actual lives, and John pretended he was getting this information from Gerbic and Edward's supposedly dead—but actually nonexistent—relatives.[209][210]
According to the magician John Booth the stage mentalist David Devant managed to fool a number of people into believing he had genuine psychic ability who did not realize that his feats were magic tricks. At St. George's Hall, London he performed a fake "clairvoyant" act where he would read a message sealed inside an envelope. The spiritualist Oliver Lodge who was present in the audience was duped by the trick and claimed that Devant had used psychic powers. In 1936 Devant in his book Secrets of My Magic revealed the trick method he had used.[162]
^ "Glossary of Key Words Frequently Used in Parapsychology" Archived 2010-12-24 at the Wayback Machine, Parapsychological Association website. "Materialization: A phenomenon of physical mediumship in which living entities or inanimate objects are caused to take form, sometimes from ectoplasm." Retrieved January 24, 2006 "Medium – Definition". Dictionary.com. Retrieved 23 March 2007.
^ M. Lamar Keene. (1997). The Psychic Mafia. Prometheus Books. p 122. ISBN 978-1-57392-161-9 "A medium still riding high in England is Leslie Flint, famed as an exponent of direct voice. William Rauscher and Allen Spraggett, who attended a sitting Flint held in 1970 in New York, said that it was the most abysmal flop of any seance they had endured. All the spirit voices sounded exactly like the medium and displayed an incredible ignorance of nearly everything pertaining to the sitters. The "mediumship " was second-rate ventriloquism."
Clairvoyance or "clear seeing", is the ability to see anything that is not physically present, such as objects, animals or people. This sight occurs "in the mind's eye". Some mediums say that this is their normal vision state. Others say that they must train their minds with such practices as meditation in order to achieve this ability, and that assistance from spiritual helpers is often necessary. Some clairvoyant mediums can see a spirit as though the spirit has a physical body. They see the bodily form as if it were physically present. Other mediums see the spirit in their mind's eye, or it appears as a movie or a television programme or a still picture like a photograph in their mind.

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."[204]
Humans have been fascinated with contacting the dead since the beginning of human existence. Cave paintings by indigenous Australians date back 28,000 years, some depicting skulls, bones, spirits and the afterlife.[3] Other cave paintings in Indonesia date back a further 10,000 years.[4] Mediumship gained popularity during the nineteenth century, when ouija boards were used by the upper classes as a source of entertainment. Investigations during this period revealed widespread fraud—with some practitioners employing techniques used by stage magicians—and the practice began to lose credibility.[5][6] Fraud is still rife in the medium/psychic industry, with cases of deception and trickery being discovered to this day.[7]