In United States v. Matti, No. 25-0148 (C.A.A.F. Feb. 27, 2026) (per Maggs, J.), the U.S. Court of Appeals for the Armed Forces attached the following Appendix concerning improper argument by counsel:
Because of the persistent problem of trial counsel using improper arguments during courts-martial, the Court offers the following non-exhaustive compendium of instances when this Court has identified areas of concern. Perhaps it will provide some helpful guidance regarding the types of improper argument that trial counsel must avoid, that defense counsel should consider objecting to, and that military judges ought to monitor.
Improper Arguments in General
1. Expressing Personal Beliefs and Opinions. “It is improper for a trial counsel to interject herself into the proceedings by expressing a ‘personal belief or opinion as to the truth or falsity of any testimony or evidence.’ ” United States v. Fletcher, 62 M.J. 175, 179 (C.A.A.F. 2005) (quoting United States v. Horn, 9 M.J. 429, 430 (C.M.A. 1980)). This is because “ ‘when the prosecutor conveys to the [members] his personal view that a witness spoke the truth, it may be difficult for them to ignore his views, however biased and baseless they may in fact be.’ ” Id. at 180-81 (quoting United States v. Modica, 663 F.2d 1173, 1178-79 (2d Cir. 1981)).
2. Engaging in Improper Vouching. Vouching may “occur[] when the trial counsel ‘plac[es] the prestige of the government behind a witness through personal assurances of the witness’s veracity,’ ” including “the use of personal pronouns in connection with assertions that a witness was correct or to be believed.” Id. at 180 (second alteration in original) (quoting United States v. Necoechea, 986 F.2d 1273, 1276 (9th Cir. 1993)); see also United States v. Voorhees, 79 M.J. 5, 12 (C.A.A.F. 2019); Horn, 9 M.J. at 429-30 (improper to use phrase “I think” when “analyzing the evidence of record . . . and in suggesting what weight ought to be given by the court to various evidence” as such “opinions are merely a form of unsworn, unchecked testimony and tend to exploit the influence of his office” (citation modified)); United States v. Knickerbocker, 2 M.J. 128, 129 (C.M.A. 1977) (describing the following as “impermissible argument”: “ ‘I think that having listened to all of the evidence in this case, there is very little doubt, in fact in my mind there is no doubt whatsoever, that the man sitting over there at the defendant’s table . . . was in fact the individual who was involved in this matter as a principal.’ ”).
3. Offering Personal Views. Trial counsel cannot make “ ‘substantive commentary on the truth or falsity of testimony or evidence’ ” or “ ‘comment[] on the defendant’s guilt and offer[] unsolicited personal views on the evidence.’ ” Fletcher, 62 M.J. at 180 (first quoting United States v. Washington, 263 F. Supp. 2d 413, 431 (D. Conn. 2003); and then quoting United States v. Young, 470 U.S. 1, 7 (1985)). Such comments “may confuse the [members] and lead them to believe that the issue is whether or not the prosecutor is truthful instead of whether the evidence is to be believed.” Id. at 181 (citing Modica, 663 F.2d at 1181).
4. Referring to Matters Outside the Record. When trial counsel departs from record evidence, “an accused’s right of confrontation [is] abridged, and the opportunity to impeach the source [is] denied.” United States v. Clifton, 15 M.J. 26, 29 (C.M.A. 1983). This misconduct manifests in a variety of scenarios. See, e.g., United States v. Norwood, 81 M.J. 12, 21 (C.A.A.F. 2021) (“Arguing an inflammatory hypothetical scenario with no basis in evidence amounts to improper argument . . . .”); Clifton, 15 M.J. at 30 (critiquing “discours[ing] on the practices and fantasies of rapists, and . . . the attitudes of unrelated rape victims”).
5. Commenting on the Accused’s Invocation of Constitutional Rights. “[I]t is improper for a prosecutor to ask the court members to infer guilt because an accused has exercised his constitutional rights.” United States v. Carpenter, 51 M.J. 393, 393 (C.A.A.F. 1999).