<P> In forensic science , Locard 's exchange principle holds that the perpetrator of a crime will bring something into the crime scene and leave with something from it , and that both can be used as forensic evidence . Dr. Edmond Locard ( 13 December 1877 -- 4 May 1966 ) was a pioneer in forensic science who became known as the Sherlock Holmes of France . He formulated the basic principle of forensic science as : `` Every contact leaves a trace '' . Paul L. Kirk expressed the principle as follows : </P>
<P> In forensic science , Locard 's exchange principle holds that the perpetrator of a crime will bring something into the crime scene and leave with something from it , and that both can be used as forensic evidence . Dr. Edmond Locard ( 13 December 1877 -- 4 May 1966 ) was a pioneer in forensic science who became known as the Sherlock Holmes of France . He formulated the basic principle of forensic science as : `` Every contact leaves a trace '' . Paul L. Kirk expressed the principle as follows : </P>
who stated that there is an exchange of materials when two objects come into contact with each other
who stated that there is an exchange of materials when two objects come into contact with each other
Dr. Edmond Locard
Dr. Edmond Locard