The magician Samri Baldwin exposed the tricks of the Davenport brothers in his book The Secrets of Mahatma Land Explained (1895).[93] The medium Swami Laura Horos was convicted of fraud several times and was tried for rape and fraud in London in 1901. She was described by the magician Harry Houdini as "one of the most extraordinary fake mediums and mystery swindlers the world has ever known".[94]
A series of mediumistic séances known as the Scole Experiment took place between 1993 and 1998 in the presence of the researchers David Fontana, Arthur Ellison and Montague Keen. This has produced photographs, audio recordings and physical objects which appeared in the dark séance room (known as apports).[188] A criticism of the experiment was that it was flawed because it did not rule out the possibility of fraud. The skeptical investigator Brian Dunning wrote the Scole experiments fail in many ways. The séances were held in the basement of two of the mediums, only total darkness was allowed with no night vision apparatus as it might "frighten the spirits away". The box containing the film was not examined and could easily have been accessible to fraud. And finally, even though many years have passed, there has been no follow-up, no further research by any credible agency or published accounts.[188]
In 1991, Wendy Grossman in the New Scientist criticized the parapsychologist Stephen E. Braude for ignoring evidence of fraud in mediumship. According to Grossman "[Braude] accuses sceptics of ignoring the evidence he believes is solid, but himself ignores evidence that does not suit him. If a medium was caught cheating on some occasions, he says, the rest of that medium's phenomena were still genuine." Grossman came to the conclusion that Braude did not do proper research on the subject and should study "the art of conjuring."[183]
From its earliest beginnings to contemporary times, mediumship practices have had many instances of fraud and trickery.[55] Séances take place in darkness so the poor lighting conditions can become an easy opportunity for fraud. Physical mediumship that has been investigated by scientists has been discovered to be the result of deception and trickery.[56] Ectoplasm, a supposed paranormal substance, was revealed to have been made from cheesecloth, butter, muslin, and cloth. Mediums would also stick cut-out faces from magazines and newspapers onto cloth or on other props and use plastic dolls in their séances to pretend to their audiences spirits were contacting them.[57] Lewis Spence in his book An Encyclopaedia of Occultism (1960) wrote:
In the late 1920s and early 1930s there were around one quarter of a million practising Spiritualists and some two thousand Spiritualist societies in the UK in addition to flourishing microcultures of platform mediumship and 'home circles'.[18] Spiritualism continues to be practised, primarily through various denominational Spiritualist churches in the United States, Canada, Australia and the United Kingdom. In the United Kingdom, over 340 Spiritualist churches and centres open their doors to the public and free demonstrations of mediumship are regularly performed.[19]