Aliases: Count Luiskovo.
First suspected: 1928, William LeQueux in Things I Know. Later Donald McCormick, Identity of Jack the Ripper.
Reasons for suspicion: Allegedly sent by the Russian Secret Police to discredit the London police. Later thrown into a criminal lunatic asylum.
Problems with candidacy: Dr. Pedachenko may never have existed. LeQueux was known to be a teller of tall-tales, and no corroborating evidence has ever been discovered.