The Scottish military doctor and pediatrician Joseph Bell, on whom the character of Sherlock Holmes was once based, was a pioneer in the field of forensics. For when Jack the Ripper started his killing spree in London, Scotland Yard asked him for advice. Nowadays however, things appear to be a little different from the days of Arthur Conan Doyle, who invented the figure of Holmes. For fiction is not based on reality; real investigators have to put up with listening to the success of fiction. There may well be similarities between the two spheres, but there are differences as well.as language and its transmission or recording. The result: Merely the same transmission path could suggest similarities, even though it is not the speakers who are similar, but their telephones. And anyone who has ever heard a voice imitator or been hoarse has reason to doubt whether voices really can be identified so clearly.

Even in the pilot film of the TV series C.S.I., which was produced by Jerry Bruckheimer, acoustics played an important role. In it, a supposed suicide turns out to be a homicide. Although a suicide message was recorded on a Dictaphone, it had not been spoken by the man who died. And in the episode The Finger, the memorable Mickey Mouse voice of an extortionist ultimately proves to be the key to solving the case.

Hermann Künzel is Professor of Phonetics at the University of Marburg and has an ear for criminal activity. He established the department of speaker recognition for the German Federal Criminal Police Office (Bundeskriminalamt, BKA). He helped solve some of the most important criminal cases of recent German history, for example the kidnapping of Jan Philipp Reemtsma and the murder of a policeman in
Holzminden, and he also helped track down the department store extortionist, Arno Funke, alias Dagobert. When someone asked him once whether he read detective novels, Künzel said: No, because when you know the reality, they seem so improbable.