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Law 101: Legal Guide for the Forensic Expert

Engagement Letter or Directive

Whether the expert works for a public laboratory or agency or is a private consultant, the expert should use a directive or engagement letter to begin the assignment. This is true even for routine assignments.

The directive or engagement letter may be an item that is discovered by opposing counsel. It may contain instructions to the expert. Under current case decisions, any information that is relied upon by the expert when formulating his or her opinion is a discoverable item, most certainly during court proceedings.

(Source: Rule 26(b)(4)(B) Federal Rules of Civil ProcedureDelCastor, supra at 407-408; Phillips, supra at 556; U.S. v. McKay, 372 F. 2d 174 (5th Cir. 1967).

For that reason, experts should take care to phrase the directive document or assignment letter carefully and avoid any hint of direction to the expert to reach a specific conclusion. The document should clearly state that the expert's conclusions must be reached only on the basis of the expert's professional opinion after full inquiry, testing and investigation.

Click on Sample Engagement Letter From Retaining Attorney and/or Sample Engagement Letter From Expert Witness (Appendix) to see sample letters from retaining attorneys and from an expert witness. The samples may be more detailed than the expert's purposes require. The expert should consider them as guidelines only but should make the use of such agreements a part of the commencement of each case.

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