In 1907, Hereward Carrington exposed the tricks of fraudulent mediums such as those used in slate-writing, table-turning, trumpet mediumship, materializations, sealed-letter reading and spirit photography.[110] between 1908 and 1914 the Italian medium Francesco Carancini was investigated by psychical researchers and they discovered that he used phosphorus matches to produce "spirit lights" and with a freed hand would move objects in the séance room.[111]
In a series of experiments holding fake séances, (Wiseman et al. 2003) paranormal believers and disbelievers were suggested by an actor that a table was levitating when, in fact, it remained stationary. After the seance, approximately one third of the participants incorrectly reported that the table had moved. The results showed a greater percentage of believers reporting that the table had moved. In another experiment the believers had also reported that a handbell had moved when it had remained stationary and expressed their belief that the fake séances contained genuine paranormal phenomena. The experiments strongly supported the notion that in the séance room, believers are more suggestible than disbelievers for suggestions that are consistent with their belief in paranormal phenomena.[51]
The poet Robert Browning and his wife Elizabeth attended a séance on 23, July 1855 in Ealing with the Rymers.[67] During the séance a spirit face materialized which Home claimed was the son of Browning who had died in infancy. Browning seized the "materialization" and discovered it to be the bare foot of Home. To make the deception worse, Browning had never lost a son in infancy. Browning's son Robert in a letter to The Times, December 5, 1902 referred to the incident "Home was detected in a vulgar fraud."[68][69] The researchers Joseph McCabe and Trevor H. Hall exposed the "levitation" of Home as nothing more than his moving across a connecting ledge between two iron balconies.[70]
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.[114] The psychical researcher Eric Dingwall observed the medium Bert Reese in New York and claimed to have discovered his billet reading tricks.[115] The most detailed account at exposing his tricks (with diagrams) was by the magician Theodore Annemann.[116]

Knowing which questions to ask a psychic takes a little thought because the questions you think you want to ask will deliver little to no results. For example, passive questions like, "Will I ever get married?" "When will I meet my next boyfriend?" are impossible to answer because the future is not bound and determined. Instead, ask questions that can aid a current situation that could affect your life down the road - like marriage. A good example would be something like, "My partner and I seem to be hitting a wall. What are the most effective tactics for improving my relationship?" You also want to avoid questions that are begging for reassurance (Should I get divorced?) or that are full of doubt. Remember that standing up for yourself will get you farther than looking for a hand to hold. Instead, ask results-driven questions like, "Why am I no longer as connected with my partner now than when I was first married." The more precise you are with your questions, the better reading you will receive, so put a pen to paper before jumping on the phone.
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.[199][200][201]
Illusionists, such as Joseph Rinn have staged fake séances in which the sitters have claimed to have observed genuine supernatural phenomena.[44] Albert Moll studied the psychology of séance sitters. According to (Wolffram, 2012) "[Moll] argued that the hypnotic atmosphere of the darkened séance room and the suggestive effect of the experimenters' social and scientific prestige could be used to explain why seemingly rational people vouchsafed occult phenomena."[45] The psychologists Leonard Zusne and Warren Jones in their book Anomalistic Psychology: A Study of Magical Thinking (1989) wrote that spirits controls are the "products of the medium's own psychological dynamics."[46]
Senses used by mental mediums are sometimes defined differently from in other paranormal fields. A medium is said to have psychic abilities but not all psychics function as mediums. The term clairvoyance, for instance, may include seeing spirit and visions instilled by the spirit world. The Parapsychological Association defines "clairvoyance" as information derived directly from an external physical source.[37]