When interviewing or preparing witnesses, it is best practice to be accompanied by another person. That person can, if necessary, serve as a witness to the witness’ statements during the interview if impeachment is later necessary. Without the third person’s presence, an attorney should be prepared to forgo impeachment of that witness based upon the interview. See AR 27-26, Rule 3.7 (Barring rare exceptions, a “lawyer shall not act as advocate at a trial in which the lawyer is likely to be a necessary witness.”); see also ABA Standards for Criminal Justice: Prosecution Function 3-3.1(g); ABA Standards for Criminal Justice: Defense Function 4-4.3(e). The ability to impeach a witness on the basis of statements at the interview can also be addressed by requesting the witness sign a statement of material facts after the interview is complete. See ABA Standards for Criminal Justice: Prosecution Function 3-3.1, Comment; ABA Standards for Criminal Justice: Prosecution Function 4-4.3, Comment.
Counsel should consider themselves responsible for the actions of any third party who is conducting the interview with them. If the lawyer is aware of conduct which would be a violation of the ethical rules were it performed by the lawyer, the lawyer should stop and correct the conduct. See AR 27-26, Rule 8.4(a) (“It is professional misconduct for a lawyer to . . . violate these Rules . . ., knowingly assist or induce another to do so, or do so through the acts of another.”).
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