David James Smith

Many forms of exorcism are both emotionally charged and intensely physical, and some overzealous exorcists have accidentally killed their patients. In a few documented cases, violent people have even used exorcism as an excuse to inflict "legitimate" physical injury on others. Even when no physical assault takes place, exorcism can cause psychological damage-particularly if the allegedly demon-possessed individual already suffers from an undiagnosed, reality-distorting mental illness.

In this article, true crime writer and Sunday Times journalist David James Smith discusses the physical and mental dangers of undergoing an exorcism. His article centers on the story of "Mary," a government clerk whose life became dramatically worse after her exorcism. Smith argues that exorcism- even when it consists of rare sessions, and does not involve obvious physical or emotional trauma-can cause long-term damage to some patients.

She was 47 years...