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  Discovered by Louis Jacques Thénard
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  Helped document crime scenes
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  First time bloodstains are corelated to injuries
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  Discovered that no two fingerprints are alike
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  Discovery that hydrogen peroxide fizzes when coming in contact with hemoglobin
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  Edmond Locard developed the Exchange Principle, stating that everything and everyone that enters a crime scene leaves some piece of evidence behind and everyone takes some piece of the crime scene with them when they leave.
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  Edmond Locard created the first crime lab in an attic with two assistants.
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  Victor Balthazard discovered that hair could be used to determine the nature of a crime.
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  Victor Balthazar discovered that gun barrels left specific sets of grooves on each bullet; the field of ballistics was formed.
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  Polygraph invented in California
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  Herbert MacDonell wrote "Flight Characteristics and Stain Patterns of Human Blood", giving him the title "The Father of Bloodstain Pattern Analysis".
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  DNA testing was discovered
