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 1910 at a séance in Grenoble, France the apport medium Charles Bailey produced two live birds in the séance room. Bailey was unaware that the dealer he had bought the birds from was present in the séance and he was exposed as a fraud. The psychical researcher Eric Dingwall observed the medium Bert Reese in New York and claimed to have discovered his billet reading tricks. The most detailed account at exposing his tricks (with diagrams) was by the magician Theodore Annemann.
According to James Randi, a skeptic who has debunked many claims of psychic ability and uncovered fraudulent practices, mediums who do cold readings "fish, suggest possibilities, make educated guesses and give options." Randi has a standing offer of $1 million US dollars for anyone who can demonstrate psychic ability under controlled conditions. Most prominent psychics and mediums have not taken up his offer.
Unlike most sites in the industry they offer all clients a money back guarantee if you’re not satisfied for any reason. You won’t get any hassles or any questions. All of the fees are stated clearly so you won’t have any surprises or additional fees. If you talk to someone for 10 minutes at $1 per minute, you’ll pay exactly what they say and that’s $10. It won’t be $10 plus some silly processing fee of $2 or $10 or whatever others set.
Many 19th century mediums were discovered to be engaged in fraud. While advocates of mediumship claim that their experiences are genuine, the Encyclopædia Britannica article on spiritualism notes in reference to a case in the 19th century that "...one by one, the Spiritualist mediums were discovered to be engaged in fraud, sometimes employing the techniques of stage magicians in their attempts to convince people of their clairvoyant powers." The article also notes that "the exposure of widespread fraud within the spiritualist movement severely damaged its reputation and pushed it to the fringes of society in the United States."