concurring in part and dissenting in part:
The majority holds that the trial court’s exclusion of additional evidence of appellant’s testimony of the victim’s prior violent acts against him was error of constitutional dimension requiring reversal of his conviction for assault with intent to murder while armed. With this part of the court’s opinion, I must respectfully disagree.1 Even assuming constitutional error, in my view, it was harmless beyond a reasonable doubt. See Chapman v. California, 386 U.S. 18, 24, 87 S.Ct. 824, 828, 17 L.Ed.2d 705 (1967); see Bassil v. United States, 517 A.2d 714, 717 (D.C.1986). Since the substance of the evidence was placed before the jury, reversal is not warranted merely because appellant’s presentation was not as exhaustive on the issue as he might have desired.
I.
Appellant Howard sought to present evidence, including his own further testimony, that (1) about three weeks prior to the date of the charged offenses, Kevin Womack, who was accompanied by Lonnie Boone, shot at him while they were in the same general vicinity; and (2) several months earlier, Womack, who apparently then believed that Howard was responsible for shooting and wounding Womack’s brother, displayed a gun in a menacing manner in Howard’s presence. Counsel for Howard proffered that Fidel Braxton could provide testimony that:
about three or four weeks before the events in this case, sometime in mid-January ... he saw Mr. Howard in the area of G Street, Southeast. Mr. Braxton was in a car with some other people, then, in fact, going to pick up Mr. Howard.
They saw Mr. Howard running down the street. He jumped in the ear and blurted out he had been shot at by Kevin [Wom-ack] and Lonnie [Boone].
Although counsel for appellant indicated that other witnesses would corroborate the testimony, no further elaboration of their anticipated testimony was proffered.
At the outset, it must be considered that the prior shooting incident was placed prominently before the jury through the testimony of three witnesses. First, the complaining witness, Lonnie Boone, testified that appellant confronted him about the alleged prior shooting, stating, “I heard you and Kevin [Womack] supposed to be — try and kill [me].” According to another witness for the government, Derrick Ross, Howard asked Boone “why they tried to creep on him and why did he tell everybody he was going to bust him,” and why “you and Kevin tried to sneak up on me that day coming from a party.” In addition to the evidence adduced during the government’s case, appellant Howard, through his own testimony, placed before the jury evidence of the prior incidents. He testified that while at the Farmer’s Market on the day of the offenses, he confronted Boone and told him, “I saw y’all. I saw y’all when y’all was — y’all had shot at me one day.” Howard further testified that he asked Boone “why did they try to kill me.” According to appellant’s testimony, Boone responded that it was Womack who had shot at him. Appellant then accused *1121Boone of being with Womack at the time, and Boone denied it. Howard testified that he acquired the weapons after the incident which occurred three weeks earlier and that he had taken the weapons with him on the night of the shooting because he knew that “these guys and Derrick [Ross] had a gun.” He made further reference to the prior incident in describing the encounter with Wom-ack and Boone on the night of the shooting. He testified again that he asked them why “they tried to do something to hurt me.” Braxton’s excluded testimony would have corroborated the prior shooting incident only to the extent that it would have established that on a prior occasion appellant believed that Womack and Boone had fired a shot at him, a fact not in dispute.
While the trial court also excluded evidence about an alleged prior occasion when Womack displayed a gun in Howard’s presence in a menacing manner, the impact of the omission of this evidence must be evaluated in light of the evidence actually presented. The defense had the benefit of the testimony of the government’s witness, Ross, that before Howard shot Womack, Womack had been making gestures that would have caused a policeman to shoot him. This testimony by a prosecution witness corroborated the accused’s statement that the shooting involved in this ease was provoked by Wom-ack’s threatening actions at the critical time. Thus, the vague statement that on a prior occasion Womack had displayed a gun in a menacing manner would have been cumulative at best on the issue of provocation.
II.
I agree with the majority, and the government concedes, that this evidence has some relevance to the third element of the offense of assault with intent to murder while armed (AWIMWA), i.e., whether there were mitigating circumstances in that appellant acted in self-defense.2 See United States v. Hobbs, 594 A.2d 66, 69 (D.C.1991); see also CRIMINAL Jury Instructions for the District of Columbia, No. 4.10 (4th Ed.1993). Of course, not every act of provocation by a victim is a legally cognizable mitigating factor. See Comber v. United States, 584 A.2d 26, 41 (D.C.1990). Where sufficient time elapses between the victim’s act of violence and the criminal offense, legal provocation will not be established. See Jamison v. United States, 873 A.2d 594, 596 (D.C.19773. The excluded evidence in this case was of the same nature and would not be legally sufficient, in itself, to support a claim that appellant acted in the heat of passion.4 Nevertheless, the evidence was relevant to appellant’s state of mind at the time that he claims he acted in self-defense, or at least under the mistaken belief that he was in imminent danger of serious bodily harm, according to his testimony. See Comber, 584 A.2d at 41 (mitigation may be found where a killing is committed under the mistaken belief that a defendant is in mortal danger). It is in this *1122context that the claimed error must be reviewed.
Extrinsic evidence that a complaining witness has committed prior violent acts against the accused is admissible to show the reasonableness of the accused’s fear of danger at the time he claims he acted in self-defense. Harris v. United States, 618 A.2d 140, 144 (D.C.1992). However, the trial court “may still exercise its discretion to limit the ‘substance, form, and quantum of evidence’ presented on the issue.” Id. at 145 (quoting Johnson v. United States, 452 A.2d 959, 960 (D.C.1982)).
The court may exclude such evidence, even when relevant, if its probative value is outweighed by the danger of its unduly prejudicial effect, Hawkins [v. United States], 461 A.2d [1025] at 1033 [(D.C.1983) ] or if the proffered evidence is cumulative, vague and uncertain. Hurt v. United States, 337 A.2d 215, 217 (D.C.1975).
Harris, 618 A.2d at 145. We review such rulings for an abuse of discretion. Id. at 144.
The trial court’s discretion in reviewing evidentiary rulings must be evaluated against an accused’s right to present a defense. Clark v. United States, 639 A.2d 76, 81 (D.C.1993). Where “the trial court’s evidentiary ruling wholly deprived the defendant of any opportunity to ... present evidence concerning ... a central issue in the case, we may only affirm if we are convinced that the error was harmless beyond a reasonable doubt.” Chapman, supra, 386 U.S. at 24, 87 S.Ct. at 828; Clark, 639 A.2d at 81. “Not every evidentiary decision of the trial court, however, necessarily implicates the defendant’s constitutional right to ... present a defense. ... If the issue is merely collateral, or where ample cross-examination has already been allowed or evidence admitted on a particular issue, trial court curtailment of the defendant’s presentation does not implicate the defendant’s Sixth Amendment rights, and we apply the less stringent test for harmless error set forth in Kotteakos v. United States, 328 U.S. 750, 765 [66 S.Ct. 1239, 1248/90 L.Ed. 1557] (1946).” Id. at 82.5 The majority concludes that evidence of the victim’s prior violent acts were central to an element of the crime charged, and therefore, the more stringent standard of Chapman applies. We need not decide whether evidence of the victim’s prior violent acts, which bear only upon the accused’s state of mind at the time of the events involved, must be viewed as a central issue in the ease because, even under the Chapman harmless error standard, the error was harmless in this case.
In the analysis under Chapman, we consider a number of factors, including the importance of the excluded evidence to the defendant’s case, whether it was cumulative, the presence or absence of other evidence bearing on the point, and the overall strength of the government’s case. See Delaware v. Van Arsdall, 475 U.S. 673, 684, 106 S.Ct. 1431, 1438, 89 L.Ed.2d 674 (1986). In this case, appellant Howard was able to present to the jury the substance of the excluded evidence through his own testimony. He testified that the victims had tried to kill him previously and that he had reason to believe that they were armed on the night of the crimes, and thus had reason to fear for his safety. Braxton, who could corroborate only appellant’s reaction to the prior violent acts of the victims and not the actual occurrence of the events, would provide only cumulative evidence according to the proffer. Appellant’s remaining proffer about potential witnesses was vague. Moreover, the central issue was what occurred on the night of the crimes. Appellant had a full opportunity to present evidence about those events, including the alleged actions of the victims which caused him to believe mistakenly that he was acting in self-defense. Appellant’s counsel had a factual basis for arguing, and did argue in closing, that appellant feared Womack and Boone because they had been trying to kill him.
*1123Further, the government’s case against appellant Howard was strong. Three witnesses supported the government’s version of the shooting, Boone, Womack, and Ross. There was physical evidence that appellant shot Womack three times in the back. Shell casings were found near Womack’s body, a fact consistent with the testimony of government witnesses, but inconsistent with appellant Howard’s testimony that he was some significant distance away from Womack at the time of the shooting. Finally, appellant’s version of events, which was apparently rejected by the jury, was somewhat implausible to say the least. Essentially, that version was that after being in a fistfight with an individual whom he believed was trying to kill him, he first obtained an automatic pistol and a sawed-off shotgun, sought him out only to make peace, and shot at Womack four times with the two weapons, hitting him in the back three times, but in self-defense. On these facts, even assuming that the damaging potential of the proffered evidence were realized, in my view, we can say that any error in exclusion of the evidence was harmless beyond a reasonable doubt.
. Except insofar as inconsistent with this dissenting opinion, I join in the other portions of the opinion of the court.
. Although self-defense was excluded as a matter of law from consideration by the jury, the issue remained viable as bearing on the element of mitigation for the offense of AWIMWA.
. In Jamison, this court sustained the trial court’s finding that the evidentiary predicate was inadequate for an instruction on manslaughter as a lesser included offense of second-degree murder where the defendant contended that he was provoked to shoot the decedent because he kept robbing him and his father. Id. The court explained:
[apparently, appellant had been robbed by [the decedent] earlier in the evening on the night of the shooting. However, the facts indicate that appellant had had plenty of time and opportunity to calm down, and that he was calm at the time he entered the bar and deliberately shot [the victim].
Id. n. 6.
. Mitigating circumstances are defined in pertinent part in the standard jury instructions used in the trial court as follows:
Mitigating circumstances exist where a person acts in the heat of passion caused by adequate provocation. Heat of passion includes rage, resentment, anger, terror and fear. A person acts upon adequate provocation if his/her action is provoked by conduct that would cause an ordinary, reasonable person in the heat of the moment to lose his/her self-control and act on impulse and without reflection. An act of violence or an immediate threat of violence may be adequate provocation, but a slight provocation, entirely out of proportion to the retaliation, is not adequate provocation.
No. 4.10; see also Comber, supra, 584 A.2d at 41.
. Under that standard, the error is considered harmless only if we can say “with fair assurance, after pondering all that happened without stripping the erroneous action from the whole, that the judgment was not substantially swayed by the error.” Kotteakos, 328 U.S. at 765, 66 S.Ct. at 1248.