1. If a victim testifies on sentencing–the rules of evidence apply the same as any other witness. Article 6b does not waive the rules of evidence when a victim testifies in sentencing. (Note, the victim gave both sworn and unsworn statements.) Failure to follow the rules (even without defense objection) gets the defense and government, and court to agree there was an error and to get a new sentencing hearing.
2. It is NEVER EVER a good idea for an accused (or one of his witnesses) to impeach the verdict. Gone are the days when we could legally seek reconsideration of the findings, even through sentencing. The legitimate tactic at the time was to present the accused’s version of events through his unsworn and then argue that the members may wish to reconsider the findings.
While impeaching the verdict is prohibited it is usually not a good idea to poke a finger in the eye of the members who have just convicted you and now are giving a sentence.
Although an accused is provided a wide berth in the content of his unsworn statement, there are certain limits in what matters he may raise before the sentencing authority. United States v. Grill, 48 M.J. 131 (C.A.A.F. 1998). Specifically, the Court of Appeals for the Armed Forces has recognized that an accused is generally prohibited from impeaching the findings of the factfinder.
United States v. Porter, No. ARMY 20110470, 2013 CCA LEXIS 946, at *8 (A. Ct. Crim. App. Oct. 31, 2013). Note, Porter arose from TC arguing that the accused had failed to impeach the verdict, “Appellant now complains that trial counsel’s repeated comments during a sentencing argument that appellant never denied the assault during his unsworn statement was improper argument. We agree.”
 There may have been a get-out for the prosecution, but it was likely not raised at trial or on appeal–else the court would have addressed it.
 See, e.g., United States v. Westcott, ACM 39936, 2022 CCA LEXIS 156 (A. F. Ct. Crim. App. Mar. 17, 2022) (unpub.) rev. denied 82 M.J. 438 (C.A.A.F. 2022).