Ezel / Ethics Opinions / DCBAR
DCBAR February 2007

Does a lawyer who serves as an expert witness for a party form an attorney-client relationship that creates a former-client conflict?

Short answer: The opinion concludes that a lawyer who serves solely as an expert witness for a party does not thereby form an attorney-client relationship with that party. As a result, Rule 1.9's bar on adversity to a former client does not prevent the lawyer from later taking a position adverse to the party for whom she testified, even in a substantially related matter. A firm that hires a lawyer as an expert should make the expert role clear at the outset and obtain the client's informed consent if the lawyer's role changes to that of co-counsel.

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Plain-English summary

Opinion 337 (published February 2007) responds to a lawyer who serves as an expert witness in bank regulatory matters and was challenged because her former firms had once done unrelated work for the opposing party. The Committee concludes that a lawyer who serves solely as an expert witness does not thereby create an attorney-client relationship with the party for whom she testifies.

The opinion reasons that a testifying expert acts like any non-lawyer expert: she is presented as an objective witness, must give opinions even if adverse to the party that called her if frankness requires, and her communications with the retaining firm are ordinarily discoverable. That role is inconsistent with the duty to advance a client's objectives diligently that defines a client-lawyer relationship (Rule 1.3). The opinion aligns with ABA Formal Opinion 97-407 and several state bars (Virginia, South Dakota, Philadelphia) that reach the same conclusion. Because no client-lawyer relationship arises, Rule 1.9 (which bars representing a person in a substantially related matter adverse to a former client) is not triggered. The opinion adds that even if serving as an expert did count as a representation, neither the inquirer nor her new firm would be disqualified on these facts, because she never personally represented the opposing party and acquired no protected information about it (Rule 1.10(b)).

The opinion then addresses role clarity. A firm that hires a lawyer-expert should define the role at the outset, for example through a written engagement letter, and ensure under Rule 1.4 that its client understands the expert's role, especially because communications with the expert are likely discoverable. If a lawyer who is co-counsel becomes an expert witness, the client must give informed consent, because confidences shared with that lawyer may now be subject to discovery and Rule 1.6(e)(1) requires consent before they may be used or revealed. If a lawyer hired as an expert is later asked to take on a consultant or co-counsel role, the lawyer must take special care that the firm and client are fully informed and expressly consent. The opinion notes additional limits: false testimony would warrant discipline under Rule 8.4; Rule 1.7(b)(4) may limit the lawyer and her firm while she serves as an expert (a conflict arising only under 1.7(b)(4) is not necessarily imputed to the whole firm under Rule 1.10(a)(1)); and a confidentiality agreement with the party for whom she testified could later limit her.

In practice

Under the D.C. rules as they stood at the time of the opinion, a lawyer who serves solely as an expert witness does not form an attorney-client relationship with the party for whom she testifies, and Rule 1.9 does not bar her from later taking a position adverse to that party. The opinion concludes a firm hiring a lawyer-expert should make the expert's role clear at the outset (for example, in a written engagement letter) and ensure the client understands it under Rule 1.4, given that communications with the expert are likely discoverable.

The opinion concludes that if the lawyer's role shifts to co-counsel or consultant, the client must give informed consent under Rules 1.6(e)(1) and 1.2(c), and that the lawyer remains subject to the Rules generally, including Rule 8.4 (no false testimony) and Rule 1.7(b)(4) (personal-interest limits). Because the opinion predates later rule developments, verify the current D.C. rules before relying on specific requirements.

Common questions

Q: Does serving as an expert witness make the lawyer the party's attorney?

A: The opinion concludes no. A lawyer who serves solely as an expert witness does not form an attorney-client relationship with the party for whom she testifies; she acts like any non-lawyer expert and must testify frankly even if adverse to that party.

Q: Can the lawyer-expert later take a position adverse to the party she testified for?

A: The opinion concludes yes. Because no client-lawyer relationship arose, Rule 1.9 is not triggered, even where the later matter is substantially related to the matter in which she testified.

Q: What should a firm hiring a lawyer-expert do?

A: The opinion concludes the firm should make the expert's role clear at the outset, ideally in a written engagement letter, and ensure under Rule 1.4 that the client understands the role, since communications with the expert are likely discoverable.

Q: What if the lawyer's role changes from expert to co-counsel?

A: The opinion concludes the client must give informed consent. Confidences shared with a lawyer who becomes a witness may be discoverable, and Rule 1.6(e)(1) requires consent before they may be used or revealed; a lawyer moving into a consultant or co-counsel role is bound by the conflict and imputation rules.

Background and rules framework

The opinion interprets D.C. Rule 1.9 (former-client conflicts) by reference to whether an attorney-client relationship exists at all, read with Rule 1.6 (confidentiality), Rule 1.7 (current conflicts, including Rule 1.7(b)(4)), Rule 1.10 (imputed disqualification), Rule 1.4 (communication), Rule 1.2(c) (limiting the scope of representation), and Rule 8.4 (misconduct). It relies on ABA Formal Opinion 97-407 and prior D.C. Opinion 316 (2002) on formation of the client-lawyer relationship.

Citations and references

Rules of Professional Conduct:

  • D.C. RPC 1.9 / Model Rule 1.9 (former-client conflicts)
  • D.C. RPC 1.6, 1.6(e)(1) / Model Rule 1.6 (confidentiality)
  • D.C. RPC 1.7, 1.7(b)(4) / Model Rule 1.7 (current conflicts; personal interests)
  • D.C. RPC 1.10, 1.10(a)(1), 1.10(b) / Model Rule 1.10 (imputed disqualification)
  • D.C. RPC 1.4 / Model Rule 1.4 (communication); D.C. RPC 8.4 / Model Rule 8.4 (misconduct)

Cases:

  • Fidelity Nat'l Title Ins. Co. v. Intercounty Nat'l Title Ins. Co., 412 F.3d 745 (7th Cir. 2005) (discoverability of materials considered by an expert)
  • In re Pioneer Hi-Bred Int'l, Inc., 238 F.3d 1370 (Fed. Cir. 2001) (same)

Other opinions cited:

  • ABA Formal Op. 97-407 (lawyer as expert witness or consultant); ABA Formal Op. 95-390
  • D.C. Ethics Op. 316 (2002); Virginia State Bar Op. 1884 (1989)

See also

Source

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