Locard's rule
The Locard's exchange principle , also Locard'sche principle known, is one of the most important principles of modern forensics . It says that no contact can be made between two objects without these leaving mutual traces. It was developed by Edmond Locard , who was a doctor and lawyer, but later turned increasingly to criminology .
Justification by Edmond Locard
As early as 1910, the then director of the French police laboratory in Lyon and co-founder of modern forensics, Edmond Locard, stated that no perpetrator could commit an act or leave a crime scene without leaving a large number of traces.
Locard put it this way:
- “Wherever he goes, what he touches, what he leaves behind, even unconsciously, all of this serves as a silent witness against him. Not just his fingerprints or his footprints, but also his hair, the fibers from his clothes, the glass he breaks, the marks of tools he leaves behind, the scratches he makes on the paint, the blood or semen, that he leaves behind or carries with him. All of this and more are silent witnesses against him. This is the evidence that never forgets. He is not confused by the tension of the moment. He is not unfocused like the human witnesses are. It is factual evidence. Physical evidence cannot be false, it cannot disguise itself, it cannot disappear entirely. Only human failure to find, study, and understand them can destroy their value. "
Significance for criminology
Locard's approaches were totally unusual for the time. They are essential to law enforcement today . Fingerprints , footprints, gunshot residue , fiber traces of blood and semen assignments are often the main burden evidence for the elucidation of numerous crimes.
The increasing importance of scientific aids for the investigation of criminal, in particular criminal processes, pushed for the creation of a new, exclusively responsible discipline, forensics . Since Locard was aware of the great importance of the forensic investigation of a crime scene and promoted it, he can be described - alongside Joseph Bell and Archibald Reiss - as the founder of forensics.
literature
- Michel Mazévet: Edmond Locard, le Sherlock Holmes français . Traboules Publishing Basis, 2006.
- EJ Wagner: The Science at Sherlock Holmes: and the Beginnings of Forensic Medicine . 1st edition. Wiley-VCH Verlag, 2008, ISBN 978-3-527-50378-0 .
Individual evidence
- ↑ a b Locard, Edmond, The criminal investigation and its scientific methods , Berlin, 1930
- ^ Pfefferli, Die Spur: Ratgeber für die Pfurenkundliche Praxis, 5th edition, Kriminalistik Verlag, Munich 2007, ISBN 978-3783200317
- ↑ Söderman, H., On the trail of crime: Memoirs of a criminalist (Mitt liv som politimann), 1957