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Ethics Ruling OK's Lawyer as Expert

Editor's Note: This article was originally published in BullsEye, a newsletter distributed by IMS Expert Services.

When a lawyer testifies as an expert witness on a party's behalf, is an attorney-client relationship created? A new ethics ruling says no, thereby freeing the lawyer to take on a new matter related to a client at her former firm.

But the opinion, published by the Legal Ethics Committee of the District of Columbia Bar, provides important cautions – both for lawyers who serve as experts and the law firms that employ them.

The opinion was issued at the request of a lawyer who serves as an expert witness in litigation involving bank regulatory and supervisory matters. She was asked to provide expert testimony on behalf of a plaintiff who had borrowed money from a savings bank that was placed in federal receivership and had its assets sold to another financial institution.

The defendant bank objected to the lawyer serving as an expert witness. The bank was a former client of a law firm where the lawyer once worked. Even though the lawyer never directly handled the bank's legal work, the bank contended that her serving as an expert witness would violate the ethical prohibition against taking on a new client in a matter adverse to a former client.

In considering these facts, the ethics panel noted that, in certain circumstances, a lawyer's service as an expert witness can create a lawyer-client relationship. "As a general matter, a client-lawyer relationship can come into being as a result of reasonable expectations of the client and a failure of the lawyer to dispel these expectations," the committee said.

Additionally, clients who consult with a lawyer, even as an expert, may expect that the lawyer will be bound by certain basic professional obligations, including the duties to maintain confidentiality and to avoid conflicts of interest.

If, however, a law firm retains an outside lawyer solely as an expert witness and the firm makes this clear to the client; then the employment creates no attorney-client relationship, the committee said.

"We believe … that if a lawyer serves solely as an expert witness on behalf of another law firm's client, and the law firm explains this role to the client at the outset, then the expert witness would not typically have an attorney-client relationship with the party for whom she may be called to testify."

In this circumstance, the lawyer's role is analogous to that of any non-lawyer expert witness, the panel explained. "The expert provides evidence that lies within her special area of knowledge by reason of training and experience and has a duty to provide the court, on behalf of the other law firm and its client, truthful and accurate information."

In fact, the lawyer's role as an expert witness carries implications that would be at odds with an attorney-client relationship. The lawyer would have to serve as an objective witness and even provide opinions adverse to the party that calls her "if frankness so dictates," the panel said.

Further, the lawyer as an expert would be subject to deposition by the opposing party, where any communications between the expert, the retaining law firm, and the client would generally be discoverable.

Other ethics panels that have considered this question have reached similar results, the opinion says. These include the American Bar Association and ethics committees in Virginia, South Dakota and Philadelphia.  

Be Clear with the Client

The ethics panel cautioned the hiring law firm to be very clear with its client about the lawyer's role as an expert. "The law firm that hires a lawyer as an expert witness should take care to avoid confusion in the mind of its client as to the different role a lawyer plays as an expert witness."

To avoid any misunderstanding, the panel recommended that the firm enter into a written engagement letter with the expert defining the relationship. The firm should ensure that its client is fully informed of the expert's role and of the discoverability of any communications between the client and the expert.

The panel further cautioned that the distinction between a lawyer's roles as expert and as counselor can easily become blurred, thereby raising additional ethical issues.

For example, a lawyer who is co-counsel in a case may become an expert witness. "Under this scenario, the Rules of Professional Conduct clearly apply, and the client needs to provide informed consent to the lawyer's changing roles," the panel said. This includes advising the client that any confidences revealed to the lawyer may become subject to discovery if the lawyer becomes an expert witness.

A reverse scenario occurs when the lawyer is hired as an expert but later asked to become a consultant or co-counsel on a different aspect of the case. "Where an expert witness morphs into a co-counsel role, the expert witness must exercise special care to assure that the law firm and the client are fully informed and expressly consent to the lawyer's continuing to serve as an expert witness with respect to some issues in the case."

As an additional consideration, the panel noted that a lawyer serving as an expert witness remains subject to the rules that govern lawyers generally. The lawyer could not, for example, testify falsely. Further, she could not take on a new client in a matter adverse to the party for whom she is serving as an expert.

Opinion 337 of the D.C. Bar's Legal Ethics Committee is available from the bar's Web site at

Robert Ambrogi is the editor of BullsEye, a monthly newsletter distributed by IMS Expert Services. IMS Expert Services is the premier expert witness and litigation consultant search firm in the legal industry, focused exclusively on providing custom expert witness searches to attorneys. To read this and other legal industry BullsEye publications, please visit IMS Expert Services at

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