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DNA - A Prosecutor’s Practice Notebook Inventory

Jurors Expect to See DNA Evidence

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Photo of a glove on the ground behind a tree plant. Caption says 'No DNA Found on Glove'
National Institute of Justice (NIJ) (see reuse policy).

The lack of DNA evidence creates reasonable doubt as to the defendant's guilt.

Due to the CSI effect, jurors expect DNA evidence to be presented. The defense may argue that the prosecution's failure to present DNA is lack of evidence which gives rise to reasonable doubt. As a rebuttal strategy, the prosecutor should educate the jury through expert testimony on the following:

  1. How DNA is transferred from a person's body
  2. What factors may prevent the transfer or detection of DNA
  3. What factors may destroy or eliminate the DNA
  4. Whether in this case it was appropriate to attempt to collect DNA for investigatory purposes

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