At the close of the nineteenth century, serial killer Joseph Vacher terrorized the French countryside for years, eluding capture while murdering more victims than Jack the Ripper. His sprawling crime wave ultimately drew in prosecutor Emile Fourquet and pioneering criminologist Alexandre Lacassagne, whose pursuit of Vacher helped push criminal investigations toward the modern era. My guest is Douglas Starr, author of "The Killer of Little Shepherds: A True Crime Story and the Birth of Forensic Science". He shares details with us about Vacher’s reign of terror and the groundbreaking investigation that led to his conviction. The author's website: https://douglasstarr.com/ Learn more about your ad choices. Visit megaphone.fm/adchoices