Page 17 - Civil Litigation

Roles of the Practitioner

The practitioner may be retained to serve in the following roles in connection civil litigation:

• Expert witness. A person qualified and, if required, disclosed to render an opinion in civil litiga-
tion. If the practitioner is formally designated as an expert witness, all work that the practitioner
has performed and all written materials and communications (including, for example, e-mails
and hand-written notes) are discoverable to the extent they

— relate to compensation for the expert’s study or testimony;

— identify facts or data that the party’s attorney provided and that the expert considered in
forming the opinions to be expressed;

— identify other documents considered or relied upon the expert in forming the opinions to
be expressed; or

— identify assumptions that the party’s attorney provided and that the expert relied on in
forming the opinions to be expressed.

(See Rule 26[b][4][C] of appendix C, "Federal Rules of Civil Procedure and Evidence.")

• Lay (fact) witness. fn 24 A person who provides relevant testimony based on his or her firsthand
knowledge.

• Percipient witness. fn 25 A person who provides relevant testimony based on his or her percep-
tions.

• Consultant. A person retained to advise about facts, issues, strategy, and other matters. The con-
sultant does not testify unless the consultant’s role subsequently is changed to an expert witness.
The consultant’s work is generally protected from discovery by legal privilege (see the "Legal
Privilege" section of this practice aid).

• Other. In addition to the roles of expert witness and consultant, the practitioner may serve with-
out limitation as a trier of fact, special master, court-appointed expert, referee, arbitrator, or
mediator.

fn 24 For example, the practitioner may be called to testify as a lay person about the performance of forensic investigation
procedures and the discovery of relevant evidence and facts prior to litigation.

fn 25 For example, the practitioner may be used as a percipient witness to express perceptions because of his or her profes-
sional and technical qualifications related to the testimony.

© 2020 Association of International Certified Professional Accountants 15