Page 20 - Expert Witness

mation and that he or she has performed no procedures to corroborate the information. Different
rules of evidence may apply in different jurisdictions, and the practitioner is not expected to be a
legal expert.

 Assumptions. An expert witness can base opinion testimony on either facts or assumptions.
Likewise, an expert witness may base assumptions on facts; presumptions from facts; or assump-
tions provided by the client, other experts, or counsel. For example, some analyses require the
use of assumptions about hypothetical situations. The practitioner should consider analyzing key
assumptions to determine whether they are reasonable and to identify the source of information.
Ultimately, the trier of fact will determine the reasonableness of the assumptions.

 Documentation. The practitioner should prepare and maintain documentation, the form and con-
tent of which should be designed to meet the circumstances of the particular engagement. The
quantity, type, and content of documentation are determined by several factors, including the
practitioner’s professional judgment, the nature of the engagement, and the directives of legal
counsel. The expert witness should understand that his or her conclusions and judgments may be
subject to discovery and cross-examination by the opposing legal counsel and evaluation by the
trier of fact. Results of research and working paper documentation (including e-mail, spread-
sheets, and correspondence) are the principal records of the procedures applied, information ob-
tained, and conclusions reached by the practitioner in the engagement. Finally, the practitioner
also may want to consider adopting a formal record retention policy in litigation matters and en-
sure that the staff are in compliance with the document retention policy or respond appropriately
to any subpoenas or agreements between the parties to the litigation.

Opinions

In situations when the practitioner is being considered, or may be ultimately asked, to serve as an expert
witness on the engagement, it is recommended that the practitioner gain an initial understanding of the
opinions expected by the client’s attorney to be formed and offered in testimony by the practitioner. At
the same time, the practitioner should be careful not to be unduly influenced by what the attorney would
like the opinion to be. It is important to note that the practitioner continue confirming this understanding
with the client because modifications are common during the course of an engagement. In most cases, an
expert opinion is exclusively that of the individual practitioner, and not of a firm or employer. If the
practitioner finds a requested opinion inappropriate, improper, or impossible, the practitioner should
promptly communicate this belief to the potential client’s attorney and not accept this particular assign-
ment of the engagement. Care should be taken by the practitioner to avoid accepting an assignment that
may result in the practitioner not being able to support an opinion.

In general, the practitioner, when serving as an expert, will be asked to opine in three broad areas: (a) li-
ability, (b) causation, and (c) damages. Liability expert opinions assist the trier of fact to determine the
fault or legal responsibility of the disputing parties. An example is a practitioner’s expert opinion about
whether management misstated financial results. Causation, sometimes referred to as proximate cause
opinions, helps the trier of fact understand to what extent an action or omission caused the claimed mon-
etary damages in the case. The most commonly requested expert opinion from the practitioner is the
quantification of monetary damages based on legally acceptable theories of remedy. In certain cases, a
trial may be bifurcated, with proceedings on liability and causation separately tried from damages.

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