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Forensic DNA Education for Law Enforcement Decisionmakers

DNA for Law Enforcement

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DNA for Law Enforcement

DNA is described as the "blueprint of life" because every normal nucleated cell in an individual's body is identical, like a blueprint for a manufactured item. The body creates, or "manufactures," cells based on a single blueprint.

DNA double-helix with half from mother and half from father. 

illustration of a male and female form making a DNA helix
National Institute of Justice (NIJ) (see reuse policy).

Basic DNA facts that all law enforcement personnel should understand are listed below:

  • DNA is inherited; we receive half from each parent
  • Identical twins have the same DNA profile
  • An individual's DNA profile stays the same for their entire life
  • An individual's DNA profile is the same in every nucleated cell
  • DNA is most stable in cool, dry conditions


To make sound investigative, evidence collection and prioritization decisions, team members including first responders, investigators and medical personnel should have a basic understanding of DNA and how DNA evidence is analyzed. 9,10

9 Illinois State Police Crime Scene Investigator Training »
10 Bureau of Justice Assistance Law Enforcement Training Database »

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