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Law 101: Legal Guide for the Forensic Expert

Items Required For Testimony

Items Required for Testimony
National Institute of Justice (NIJ) (see reuse policy).

It is hoped that the expert will have the opportunity to discuss the details of the testimony with the proffering attorney ahead of time, either in person or by telephone. At times, because of circumstances beyond the expert's control, this may not occur. If schedules do not permit this, the expert should request an arrival time that provides adequate pretrial preparation before the expert is expected to testify. 

For this pretrial conference, and for the actual testimony, the expert should bring:

  • Copies of all reports generated as a result of testing.
  • Any reports generated after reviewing work performed by another expert.
  • Copies of the entire case file associated with the work performed on the case.
  • Documentation of any communication, including e-mail with others in the case (e.g., law enforcement, other laboratory personnel, attorneys).
  • Any items of evidence still in the expert's possession about which the expert may testify.
  • Photographs or other documentation of items of evidence tested that may no longer be in the expert's possession.
  • Complete chain of custody documentation.
  • Copies of the expert's curriculum vitae or résumé.

Other items the expert may or may not bring:

  • Copies of the laboratory's quality assurance/quality control (QA/QC) documentation.
  • Copies of (or at least the results of) any proficiency tests taken.
  • Copies of the laboratory's standard operating procedures (SOPs).

If in doubt about whether or not to bring these additional items, the expert should:

  • Consult with the retaining attorney for the case.
  • Confer with the lab supervisor.
  • Bring the additional items in case the expert is asked to provide them.

In certain circumstances, the expert may not have an opportunity to discuss details of the testimony with the retaining attorney in advance. The expert must be prepared for this possibility. (More information about self-preparing for testimony is provided in Pretrial.)

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Date Created: September 1, 2023