Atlas Obscura found an interesting patent in the American archives dated 1930. Its author, Helen Shelby, was convinced of the effectiveness of the symbiosis of the latest technology and ancient beliefs of people in the supernatural. She suggested building a machine for interrogating criminals that would look and behave like a living corpse.
Shelby called her invention "An apparatus for obtaining confessions of a crime and photographing them." It was assumed that the animated skeleton would frighten the person being interrogated and demand confessions (the hidden investigator would speak for him). Built-in photo and sound recording tools will automatically capture the suspect's behavior to form evidence. All the necessary technologies already existed at that time, and a talented engineer could combine them in one apparatus.
But why did Shelby believe that a criminal would be more afraid of some skeleton than a living investigator? Because the previous 20s were the heyday of spiritualism - and it was often used for selfish purposes. Fraudsters generously paid inventors to create "fake machines" that, with the help of smoke, lights and sounds, imitated the appearance of otherworldly forces. The level of psychological processing of clients was so high that millions of people firmly believed in the possibility of contact with ghosts. And those who did not believe or tried to expose the criminals sometimes became their victims with the help of quite material means.