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Diabolical Possession and the Case Behind The Exorcist, by Sergio A. Rueda

Cover of Diabolical Possession and the Case Behind The Exorcist
Publication Details: 
McFarland, ISBN: 9781476673844.
Publish date: 
October, 2018

This book is based on a Ph.D. dissertation (apparently unpublished) about the factual basis for William Peter Blatty’s best-seller The Exorcist which inspired a very well-known horror movie which got a lot of publicity in 1973. Stanley Krippner has written a Foreword in which he recalls that he once met the director, William Friedkin, and gave him advice. Allegedly, Friedkind, once said “I could never have made The Exorcist the way I did without Dr. Krippner’s advice.” The author Sergio Rueda is a Pentecostal minister. He believes that his book is written in a “scholarly scientific style” but that it should nevertheless be accessible to laymen. Unfortunately, the book is repetitive and would have benefited from editing. In addition, sometimes there are no citations to sources.

Rueda reveals that prior to his research he “anticipated that this investigation would finally lead me to the confirmation of what I had previously believed, namely, that demonic possession existed and exorcism was the means to rid the possessed people of the demons and to cure them” (p. 13). He became interested in finding out the truth when at the Foundation for Research on the Nature of Man (FRNM) he came across correspondence from 1949 between J.B. Rhine and Rev. Luther Miles Schulze concerning the case. As Rueda came to realise the 1973 movie, was “a distorted and exaggerated version” (p. 17) of what really occurred. Some have written about the real case before Rueda, including Thomas Allen (1993) who claimed that he had access to a diary kept by one of the priests. Rueda gave a presentation about the results of his research at the annual convention of the Parapsychological Association (Rueda, 2006).

In reality the person allegedly possessed was a 14-year old boy named Ronald. On March 21, 1949, Schulze wrote to Rhine and described poltergeist phenomena occurring around him. Phenomena had apparently started to occur in January, when a scratching noise of unknown cause was often heard during the evening until midnight. More phenomena followed which the family attributed to a deceased aunt thought to have answered questions by raps during a séance. When Ronald was at Schulze’s home Schulze observed poltergeist phenomena and subsequently organized prayer circles. Rueda interviewed Schulze and also managed to get an interview with one of the participants who recalled that she had seen Ronald levitate about two inches above his bed and act as if he was possessed. Since prayer circles did not appear to help other attempts were made to get rid of the phenomena and the boy was given anti-epileptic medication. A Catholic priest, Father Albert Hughes concluded it was a case of demonic possession to be cured by exorcism.

The first exorcism was in vain, the second exorcism was a protracted affair detailed by Rueda who extensively quotes from a document written at the time. It is evident that whatever really occurred in 1949 was something more than a simple prank. If Ronald was just pretending he was certainly persistent and dedicated. Marks, scratches and writing appeared on Ronald’s body several times (though none seem to have been photographed) and he behaved as if possessed. Among the messages that appeared on his body was ”Go to St. Louis” where his recently deceased favorite aunt had lived (that is, according to his mother, when Schulze looked he only saw scratches). Writing would occur spontaneously in response to questions posed by his mother: Rueda thinks “it seems plausible that Ronald may have manufactured the marks himself” (p.78), yet Rueda writes that messages appeared even when Ronald’s hands were seen. Furthermore, he argues that “... as preposterous as this hypothesis may sound, it is quite possible that Ronald’s father may have helped him set up an electrical mechanical device under the floor ... which could produce scratching sounds” (p. 80). Motivation for the boy to commit fraud was that he did not want to go to school where he had problems, it is suggested that he was being bullied.

It is, however, important to remark that the fraud hypothesis cannot by itself explain all the phenomena in this case, such as the spontaneous marks that later appeared on the boy before several witnesses - particularly those that appeared on his body during the exorcism that took place in St. Louis at the Alexian Brothers Hospital (p. 87).

Despite some trouble at school Ronald appeared to be a normally introverted though somewhat high-strung, boy - the two psychiatrists that were consulted in 1949 did not report anything unusual, though little is known about their evaluations. At this point in time Rueda can naturally just speculate about Ronald’s psychology, which he does. Rueda suspects that the boy was “suffering from conversion reaction and coprolalia (the excessive and uncontrollable use of foul language” (p. 93). Religious folks will likely draw attention to the fact that Ronald had played with a Ouija board several times. Rueda argues that Ronald was probably a poltergeist agent (that is, the phenomena followed him) and that suggestion may have made him act as if he was possessed. He thinks the case “constitutes a good example of how superstition and belief in demonic possession may combine to create a real case of demonic possession” (p. 113).

… the main purpose of this book is to provide as much information as possible on the most famous case of demonic possession in history. Consequently, the reader can gain a better understanding of what really lies behind the actual case and reach his or her own conclusions regarding the authenticity of this case (p. 151).

Rueda himself believes that fraud accounts for about 20 percent of the reported phenomena and that the psychological hypothesis accounts for about 35 percent. He also considers it likely that Ronald was a real poltergeist agent. Naturally he discusses the demonic possession hypothesis too, but he finds it very improbable in this case although not impossible. These kind of cases are often messy and trying to sift fact from fiction long after the events occurred is difficult. In his search for answers Rueda consulted clinical, religions and parapsychological literature. However, he appears to be unaware of Mark Opsasnick’s (1998) investigation which paints Ronald in a different light. The results of his investigation were first published in Strange Magazine, which is somewhat obscure, but later Opsasnick (2005) published a short book too. To his credit Rueda include two of his interviews plus the letters between Schulze and J.B. Rhine and more as appendixes. The book is just about 160 pages, the rest consists of appendixes, references etc. Although the book is repetitive, not particularly well written, and necessarily rather speculative it must be acknowledged that it is informative.


Allen, T. (1993). Possessed: The True Story of an Exorcism. London: Doubleday.
Opsasnick, M. (1998). The Haunted Boy of Cottage City: The Cold Hard Facts Behind the Story that
   Inspired The Exorcist
. Strange Magazine, 20.
Opsasnick, M. (2005). The Real Story Behind the Exorcist. Philadelphia: Xlibris.
Rueda, S. A. (2006). A medical-psychological approach to the possession case behind William
   Blatty’s The Exorcist. Proceedings of the 49th Annual Convention of the Parapsychological
(pp. 216-225)