dissenting:
It is difficult for me to conclude on the present record, without benefit of a hearing, that defense counsel’s decision to call Mattison as a witness was not deficient. If defense counsel’s performance was deficient, relief is warranted because the record supports the conclusion that there was resulting prejudice under Strickland v. Washington, 466 U.S. 668, 104 S.Ct. 2052, 80 L.Ed.2d 674 (1984). But for Mattison’s testimony, this case came down to a credibility contest between the complaining witness, who was impeached as a drug abuser, and the appellant. Although there was physical evidence that a sexual assault had occurred in the basement of the house where Sothern lived on the second floor and that the complaining witness had been injured, there was no physical evidence that linked appellant to that assault. When Mattison testified on direct, however, he said that appellant had done a sex-for-drugs deal with the complaining witness, engaged in sex with her and had then encouraged Mattison to participate as well. This testimony not only was directly contradictory to the defense that trial counsel announced during opening argument, that appellant had not engaged in any sex at all with the complaining witness, but it also corroborated part of the complaining witness’ testimony and established that appellant possibly had a key to the basement. Moreover, the government’s cross-examination of Mattison completely devastated his story that whatever sex had occurred was consensual because Mattison was effectively impeached with his plea hearing testimony that the complaining witness “was scared and frightened,” that the sex was against her will, and that Mattison left the scene because something “wrong” was going on in the basement involving what Sothern was doing to the complaining witness. The government effectively cross-examined Mattison as to his unwillingness to incriminate appellant, even though Mat-tison had already plead guilty and been sentenced, because, as Mattison stated, a “snitch” is someone “who dies very quickly.” During closing argument, defense counsel asked the jury to consider that the “only” evidence against Sothern was the complaining witness, who was bent on revenge for a drug deal gone wrong, but that her revenge should be directed against Mattison, because “the Government has woefully failed to show any connection that [Sothern] had.” Not surprisingly, in rebuttal the government took advantage of counsel’s question and answered it for the jury: “Is there evidence that [Sothern] was involved? Sure, there was, ladies and gentlemen. And it didn’t just come from Government witnesses. It came from the defense’s own witness, Mr. Major Lee Mattison.” Therefore, I cannot conclude that Mattison’s testimony did not seriously prejudice appellant. See Strickland, 466 *940U.S. at 696, 104 S.Ct. 2052 (“[A] court making the prejudice inquiry must ask if the defendant has met the burden of showing that the decision reached would reasonably likely have been different absent the errors”).
I also do not think that the prejudice from Mattison’s testimony can be laid at the feet of the appellant, as suggested by the trial court and the majority on appeal. Inconsistencies between the testimony of appellant and Mattison are not the appellant’s “fault.” To state otherwise suggests that Sothern should have “conformed” his testimony to Mattison’s version, even if appellant believed it was untrue. Moreover, Sothern’s testimony was not the first inconsistency between the defense case and Mattison’s version of events; a lot of harm had already been done before Soth-ern testified because, during opening argument, defense counsel had vouched for Mattison’s credibility and had previewed Mattison’s testimony for the jury: that it was he, not appellant, who had engaged in sex — consensual or otherwise — with the complaining witness, and that it was “something Mr. Sothern had nothing to do with whatsoever.” When Mattison testified on direct, however, he stated that Sothern engaged in sex with the complaining witness first and then encouraged Mat-tison to do so as well; and during cross-examination, Mattison’s testimony went farther, clearly incriminating Sothern in rape and kidnaping.
Even though there is a “strong presumption that counsel’s conduct falls within the wide range of reasonable professional assistance,” Strickland, 466 U.S. at 689, 104 S.Ct. 2052, the reasonableness of defense counsel’s performance in deciding to call Mattison to testify at trial requires careful scrutiny as it was determinative of the § 23-110 motion in light of the strong prejudice that resulted from Mattison’s testimony. The trial court reasoned that defense counsel’s performance was not defective because he had a good reason to call Mattison to rebut the kidnaping charge and, after interviewing Mattison pre-trial, was satisfied that he would not incriminate Sothern in the rape.1 The trial court commented that “if the jury had credited Mr. Mattison’s version of the acts (namely that the entire encounter was consensual), defendant would have been acquitted on all charges.” This view is too rosy to be accepted without inquiry, for Mattison’s version of a consensual sexual encounter was on its face subject to serious doubt by the jury, which had been informed that he had plead guilty to sodomy and attempted rape as a result of that encounter. Apparently, defense counsel also expected that, by limiting the direct examination, he could prevent the government from eliciting the damaging testimony that came out during its cross-examination of Mattison. The government’s cross-examination of Mattison, however, was cldarly within the scope of direct examination, ie., the events on the day of the rape. Under Strickland, deference to trial counsel’s reasonable tactical decisions is required; bowing to a call which on its face is mere wishful thinking, is not.
In the order denying the § 23-110 motion, the trial court relied on the statement in defense counsel’s affidavit that appellant insisted that Mattison be called as a witness, even after counsel had conveyed his misgivings about calling Mattison to the *941stand.2 Appellant disputes in his affidavit that counsel told him how Mattison’s testimony could hurt him.3 As there was no hearing conducted to resolve this material factual dispute, and neither affidavit is incredible on its face or in the context of other evidence of record, the trial court could not rely on one affidavit over another. Nor can we, for to do so is to engage in the type of appellate fact-finding that this court has regularly eschewed as outside its province in the allocation of judicial authority. See Dickerson v. United States, 677 A.2d 509, 511-12 (D.C.1996) (“It is incumbent upon us, in this case as in any other, to eschew appellate fact-finding.”); Speyer v. Barry, 588 A.2d 1147, 1156 (D.C.1991) (“appellate courts are not equipped for fact-finding”). We both require and defer to the fact and credibility findings of trial judges precisely because it is within their province to hold evidentiary hearings and assess a witness’ demeanor in making such findings. See In re S.G., 581 A.2d 771, 775 (D.C.1990) (“This court may not usurp the prerogative of the judge, as the trier of fact, to determine credibility....”); Davis v. United States, 564 A.2d 31, 40 (D.C.1989) (noting “general principle that appellate courts should defer to the trier of fact because, as a functional matter, the trier of fact is better positioned to make such findings”).
The statute provides that “[ujnless the motion and files and records of the case conclusively show that the prisoner is entitled to no relief, the court shall grant a prompt hearing thereon.” D.C.Code § 23-110(c) (1996 Repl.). Here, the motion and trial record raise troubling questions about counsel’s performance. It may be that, supported by counsel’s reason to call Mattison to rebut the kidnaping charge and the assertion in trial counsel’s affidavit that he interviewed Mattison and was satisfied that he would not incriminate appellant, the decision to call Mattison properly can be characterized as a reasonable tactical decision, though certainly not one without risk as the ensuing trial proved. See McKinnon v. United States, 644 A.2d 438, 444 (D.C.), cert. denied, 513 U.S. 1005, 115 S.Ct. 523, 130 L.Ed.2d 428 (1994) (noting “tactical decisions which may go awry at trial do not constitute ineffectiveness”) (quoting Carter v. United States, 475 A.2d 1118, 1123 (D.C.1984), cert. denied, 469 U.S. 1226, 105 S.Ct. 1222, 84 L.Ed.2d 362 (1985)). But where the issue of deficient performance is so close, the trial court relied on material facts that are disputed on the written submissions, and the prejudice to appellant was serious, the trial court must hold a hearing.
I would reverse and remand for a hearing.
. Defense counsel’s affidavit submitted by the government in opposition to Sothern’s § 23-110 motion is very carefully worded on this issue, stating that
It was my opinion that [Mattison] would make a reasonably credible witness for the defense and would not testify that [Sothern] ever had sex with [the complaining witness] against her will.
(Emphasis added.)
Counsel is correct that consensual sex would not have incriminated appellant, but it certainly contradicted counsel's opening argument that Sothern “had nothing to do with” sex with the complaining witness and, presumably, undermined the defense’s credibility.
. Defense counsel's affidavit states:
Prior to presenting the testimony of Mr. Mattison I discussed with defendant that I was concerned about what Mattison would say took place in the basement. I knew Mattison would state that the sex was consensual, and that he — Mr. Mattison, had had sex with her. I told defendant about my concerns but defendant was adamant that he wanted Mattison to testify.
. Appellant’s affidavit states:
I had no idea what Mr. Mattison’s testimony would be and my lawyer never told me. If I knew beforehand what his testimony would be, I would never have wanted him to testify on my behalf.