Spirit Photography, Psi Phenomena
Standing
Concerns Key Experiment
Currently States At Mumler's 1869 New York fraud trial, witnesses including P. T. Barnum demonstrated that ordinary double exposure could produce a convincing spirit photograph; Mumler was acquitted for lack of definitive proof but his reputation never recovered.
William Mumler began selling commercial spirit photographs, portraits showing a sitter alongside a faint secondary image said to be a deceased loved one, from 1861 in Boston, the origin of the practice. Mumler was tried for fraud in New York in 1869, and Louis Kaplan's The Strange Case of William Mumler, Spirit Photographer (2008) documents that although Mumler was acquitted on the specific criminal charge, expert witnesses at the trial, including the photographer and showman P. T. Barnum, demonstrated in court the conventional darkroom double-exposure technique capable of producing the same effect. The method presented at trial was a direct technical demonstration reproducing Mumler's results by ordinary photographic means, distinct from proving Mumler had used that specific method on any given plate. Kaplan records the presiding judge stated for the record he remained personally convinced deception was likely despite the acquittal, which turned on the prosecution's inability to prove Mumler's specific method beyond reasonable doubt. Because a conventional method demonstrably capable of the same result was shown in court, the key experiment is recorded as debunked notwithstanding the acquittal.
Source The Strange Case of William Mumler, Spirit Photographer, Louis Kaplan