"Victoria Helen McCrae Duncan (25 November 1897 – 6 December 1956) was a Scottish medium best known as the last person to be imprisoned under the British Witchcraft Act of 1735"

Wikipedia:

During World War II, in November 1941, Duncan held a séance in Portsmouth at which she claimed the spirit materialization of a sailor told her HMS Barham had been sunk. Because the sinking of HMS Barham was revealed, in strict confidence, only to the relatives of casualties, and not announced to the public until late January 1942, the Navy started to take an interest in her activities. Two lieutenants were among her audience at a séance on 14 January 1944. One of these was a Lieutenant Worth who was not impressed as a white cloth figure had appeared behind the curtains claiming to be his aunt but he had no deceased aunt. In the same sitting another figure appeared claiming to be his sister but Worth replied his sister was alive and well. Worth was disgusted by the séance and reported it to the police. This was followed up on 19 January, when undercover policemen arrested her at another séance as a white-shrouded manifestation appeared. This proved to be Duncan herself, in a white cloth which she attempted to conceal when discovered, and she was arrested.

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She was initially arrested under section 4 of the Vagrancy Act 1824, a minor offence tried by magistrates. The authorities regarded the case as more serious, and eventually discovered section 4 of the Witchcraft Act 1735, covering fraudulent "spiritual" activity, which was triable before a jury.

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Duncan's trial for fraudulent witchcraft was a minor cause célèbre in wartime London. Alfred Dodd, an historian and senior Freemason, testified he was convinced she was authentic. The trial was complicated by the fact that a police raid on the séance in Portsmouth, leading to the arrest of Helen Duncan, yielded no physical evidence of the fraudulent use of cheesecloth, and was therefore based entirely on witness testimony, the majority of which denied any wrongdoing. Duncan was barred by the judge from demonstrating her alleged powers as part of her defence against being fraudulent. The jury brought in a guilty verdict on count one

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Duncan was imprisoned for nine months, Brown for four months and the Homers were bound over. After the verdict, Winston Churchill wrote a memo to Home Secretary Herbert Morrison, complaining about the misuse of court resources on the "obsolete tomfoolery" of the charge.

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On her release in 1945, Duncan promised to stop conducting séances, but she was arrested during another one in 1956.

*Previously: These look like witches' towers in real life