(dissenting). I would reverse the decision of the court of appeals and affirm the circuit court's decision to exclude the contested evidence in this case. I dissent because: (1) the circuit court's decision to exclude the testimony was not an abuse of discretion, and (2) any error that may have occurred was harmless error.
The majority concludes, from its review of the record, that the circuit court abused its discretion because the majority believes that the circuit court held the mistaken view that the law allowed only the defendant to testify about the victim's prior specific violent acts to prove the defendant's state of mind, (majority op. at 101). The majority bases this conclusion on its interpretation that the circuit court did not speak in terms of excluding the evidence as a matter of discretion, that the circuit court expressed no valid reason for its decision to exclude the testimony other than its reference to a rule, and on comments made by the assistant district attorney. The majority does not give proper deference to the circuit court, and ignores a guiding principle enunciated in Loomans v. Milwaukee Mutual Ins. Co., 38 Wis. 2d *111656, 662, 158 N.W.2d 318 (1968), "[t]he review of an order which rests on legal discretion is limited to abuse and this court will look for reasons to sustain the trial court rather than make an independent review of the question as we do for legal error."
Reviewing the record in light of this threshold inquiry, the circuit court judge excluded the additional evidence not because he misunderstood the law, but rather because he did not believe that the additional evidence would be relevant or probative unless the State actually challenged Daniels' (the defendant's) knowledge of the victim's prior violent conduct. Because the standard is abuse of discretion, this court may not simply substitute its discretion for that of the circuit court on the question of relevance. In re Johnson, 9 Wis. 2d 65, 75, 100 N.W.2d 383 (1960). Reviewing courts should examine the record to determine if the circuit court properly exercised its discretion.
The question of whether the defense would be allowed to introduce extrinsic evidence to support the defendant's statements concerning the victim's prior conduct was raised repeatedly during the trial. Comments by the circuit court judge indicate that he considered this matter to be one of his discretion. First, the following discussion occurred on the second day of the trial while the jury was excused:
Court: Upon counsel's assurance that defendant will take the stand and upon risk of having it stricken if not, I will permit you to ask the witnesses if they have an opinion as to the defendant's reputation for violence.
Ms. Buker
[Assistant District Attorney]: You mean the victim's. You mean the *112victim's reputation.
Court: Yes. That's all until after the defendant testifies.
Mr. Robson [Defense Counsel]: And then at some point,Judge, am I going to be permitted under the McMorris and—
Court: When the defendant testifies if he intends to go into other prior acts of violence, I have already indicated we will have a hearing outside of the presence of the jury and the Court has discretion under the law as to what is or is not admissible. I am well aware of the law that once the plateau has been reached where there is factual evidence for the defense of self-defense, that the defendant may testify as to prior acts of violence known to him at the time of the event in question . . .. That's the law as I understand it. And if you can show me anything to the contrary I will be happy to look at it, counsel.
Mr. Robson: . . . am I prohibited from inquiring of the victim whether on a certain occasion he in fact bragged about what he had done in the way of causing a beating death?
Court: When the victim testifies, you will be precluded from doing that at that time, counsel, until after the defendant testifies. And then we will reach the problem as it may exist at that time. But you can ask this witness if he *113has an opinion as to the defendant's use of violence and if he has an opinion he can give that opinion. That's all. . .. All you can ask this witness is if he has a reputation as to the victim's — as to the victim's violence and if he has, you can have him state that opinion. That's all you are going to get out of this witness. That's all you are going to get out of any witnesses until the defendant testifies. That's the law and that's the way we are going.
(Emphasis added.)
This discussion indicates that the judge did not have a closed mind in regard to admitting evidence other than the defendant's own statements, but rather that this evidence would not be considered until after the defendant had himself testified and raised a factual basis for his claim of self-defense.
Secondly, the circuit court judge allowed the following question from the defense attorney of a state witness, A1 Clay Reynolds:
Q: And do you have an opinion, sir, from your knowledge of him over the years that you have known him of his reputation for violence or peaceableness?
A: Well, over the years I know him like playing football.
Court: Well, do you have an opinion? Yes or no?
A: No.
By Mr. Robson:
Q: You don't have any opinion?
A: I never really paid an amount of attention.
*114A third example demonstrating that the court exercised its discretion is the testimony of Winnebago County Deputy Coroner Swanson. Swanson testified under an Offer of Proof, outside of the presence of the jury that the victim was listed as the person who had caused the death of a Mr. Jacobson. The circuit court judge allowed, in addition to the Offer of Proof, the admission of documents concerning the death of Mr. Jacobson. The judge then stated:
Court: As I understand it, if it should be necessary and the Court should decide that this testimony is relevant and germane to an issue being tried, we could advise the jury that the coroner was here and testified and was cross-examined and have her read the testimony.
Ms. Buker: . . . I'm not agreeing that anything he said today could under any circumstances be admissible.
Court: I understand your position. But [if] the court should disagree with you, then I assume you would agree that we use that portion of the transcript the court found proper.
(Emphasis added.)
The coroner's report and testimony clearly referred to a prior incident of the victim's conduct. The circuit court judge, in this exchange, demonstrated a willingness to admit relevant extrinsic evidence of the victim's prior conduct, beyond the testimony of the defendant.
Finally, during the defendant's testimony, the defense counsel attempted to elicit what the defendant knew about the victim's prior violent conduct. In response to an objection from the State, the court stated: "I think we have reached the plateau where it's arguably *115a question of whether or not the defendant acted in self-defense. Why would not evidence of his knowledge of prior violent acts be relevant and material?" (Emphasis added.) The circuit court judge then allowed the defendant to testify to six prior instances of the victim's violent conduct outside of the presence of the jury. The judge then stated:
And the law as I understand it permits the defendant to testify as to specific prior instances of violence on the part of the alleged victim. All of the specific acts that the witness has testified to occurred if I recall his testimony within the last year-and-a-half. The state of mind of the accused of course is an issue in this matter. I will permit the testimony. It may possibly enlighten the jury on his state of mind at the time of the fray and determine whether or not he acted as a reasonably prudent person under the same or similar circumstances. Which is the test under self-defense. You of course will be permitted to call rebuttal witnesses if you wish, Miss Buker.
In this statement, the judge demonstrates that evidence is admissible if it is relevant to the test of whether the defendant acted as a reasonably prudent person under the same or similar circumstances.
The circuit court judge did not believe that extrinsic evidence was inadmissible, but rather that it was not relevant unless the State took issue with the defendant's recitation of the victim's prior violent conduct. The judge stated:
Well, we already have the specific prior instances of alleged violence on the part of the victim which the defendant claims he knew of at the time of the offense. And that those were admitted to go to his state of mind at the time of the alleged offense in question. Unless and until the State puts those in *116issue, why do we need any additional testimony? ... The issue is whether or not knowing those things he acted as a reasonably prudent person would under the same or similar circumstances. We already got them in with his testimony which at this point is uncon-tradicted . . .. Well, I think we have gone as far as the rule allows which permitted you to show that the defendant allegedly knew of the specific prior instances of violence on the part of the victim.
The majority concludes that this last sentence indicated that the judge had a mistaken view of the law, (majority op. at 102). However, as the full statement indicates, the judge based his decision on his belief that, until the State actually challenged Daniels' knowledge of the victim's prior violent conduct, additional testimony about prior instances of the victim's prior conduct was irrelevant. Additionally, in response to the defense counsel's concern that the State may attempt to show that the defendant's statements were self-serving or should be discounted, the court stated: "Well, unless and until the State does that, counsel, I am not prepared to permit any further testimony in that regard." These statements suggest that the judge did not believe that the testimony or evidence was probative unless there was some question raised as to the defendant's truthfulness. These statements do not suggest that the judge was misapplying the McAllister rule. McAllister allows the introduction of other evidence at the discretion of the trial court. McAllister v. State, 74 Wis. 2d 246, 250-51, 246 N.W.2d 511 (1976). It does not suggest that the court must allow extrinsic evidence to bolster extensive and uncontra-dicted testimony of the defendant. On the contrary, it is the duty of the court to exclude such evidence when it is offered to prove that the victim acted in conformity with prior violent behavior. McAllister, 74 Wis. 2d at 251.
*117The defendant's testimony was not the only evidence admitted concerning the victim's propensity for violence. The circuit court judge also allowed the testimony of Thomas Ewing for the purpose of establishing that the victim had a reputation for violence.
The record demonstrates that the circuit court judge was interested in restricting evidence only to that which was relevant and material, and that he did not wish to try collateral issues in the case. During one discussion between the parties and the court concerning prior convictions of the parties he stated: "I am not going to open the collateral can of worms as to whether or not I am going to attempt to try all five of these issues in this case." He then went on to add:
Well, the only question is the state of mind. He's testified that these events occurred and he was aware of them. Whether the jury chooses to believe that or not is a question of credibility on the part of the defendant.
Evidence of the narrowness with which the majority addresses this issue is the manner in which the majority dismisses two of the State's arguments explaining why the judge acted within his discretion: (a) to prevent a series of mini-trials and (b) to prevent further testimony of the victim's bad character and lead the jury to believe that the victim "got what he deserved," and acquit the defendant on those grounds. See Cleary, McCormick on Evidence, sec. 193 (3d ed. 1984).1 The majority suggests *118that the circuit court could have given a limiting instruction, (majority op. at 107 n.9), although such an instruction may be of limited utility once the "cat is out of the bag.” Admission of additional evidence about the victim's prior instances of conduct could have easily led the jury to believe that the victim acted in conformity with the prior violent behavior. See McAllister, 74 Wis. 2d at 251. The defendant was allowed to testify about the victim's behavior in six prior instances. The State did not dispute this conduct. The jury heard a third-party witness, Thomas Ewing, testify that the victim had a reputation for violence, and "sometimes [goes] off" like a "little old firecracker." They also heard Ewing testify that Gregg sometimes did "crazy" things, and state that it happened to him one time. The jury heard Roland Brent's preliminary hearing testimony that he had seen Gregg pull a gun in the defendant's presence in the past. Based on the extent of this testimony and the fact that the State did not contest Daniels' testimony about Gregg's prior violent conduct, the circuit court judge used his discretion in deciding that additional evidence would be irrelevant.
This court will affirm a discretionary order if there appears any reasonable basis for the trial court's decision. Littmann v. Littmann, 57 Wis. 2d 238, 250, 203 N.W.2d 901 (1973). The majority properly cites Hedtcke v. Sentry Ins. Co., 109 Wis. 2d 461, 472, 326 N.W.2d 727 (1982), for the proposition that if a circuit court judge bases the exercise of his discretion upon a mistaken view of the law, his conduct is beyond the limits of discretion. *119The applicable language states, "... if this court's review of the record indicates that the circuit court applied the wrong legal standard, this court will reverse the circuit court's decision as an abuse of discretion." Hedtcke, 109 Wis. 2d at 471-72. This language indicates that this court should review the record to determine, based on this review, whether the circuit court applied the wrong legal standard. Even if the circuit court had had a mistaken view of the law (which I do not concede), this would not be grounds for automatic reversal. "A reviewing court is obliged to uphold a discretionary decision of a trial court, if it can conclude ab initio that there are facts of record which would support the trial judge's decision had discretion been exercised on the basis of those facts." Schmid v. Olsen, 111 Wis. 2d 228, 237, 330 N.W.2d 547 (1983). The majority agrees that this court may engage in its own examination of the record and determine whether the facts in the record support the circuit court's decision, when the circuit court sets forth no reasons or inadequate reasons for its decision, (majority op. at 103). I believe that any additional testimony about the victim's prior violent conduct would have been cumulative, and only marginally probative. Because the additional testimony would only have reiterated what the jury had already heard, I believe that there was a strong possibility that this testimony would go beyond the legitimate purpose of establishing what the defendant believed to be the violent character of the victim, and serve only to prove that the victim acted in conformity with his prior violent behavior. McAllister, 74 Wis. 2d at 251.
Interestingly, the majority indicates that this additional evidence would not necessarily have to be admitted at a new trial. The majority suggests that the circuit court could refuse to admit this proffered evidence by *120articulating a reasonable rationale supported by the facts in the record, (majority op. at 108). In other words, had the circuit court stated, "although I am permitted to admit other testimony concerning the victim's prior violent conduct, at my discretion I find it to be marginally probative and cumulative" this court may not have found an abuse of discretion. I find this mechanistic application of the Hedtcke principle to be troubling and inconsistent with the Loomans directive that this court should look for reasons to sustain the trial court.
I also disagree with the court that the error was not harmless. The circuit court judge gave a jury instruction on self-defense. He stated:
For the defendant's conduct to be privileged under the law of self-defense, the defendant must have reasonably believed that there was an actual or imminent unlawful interference with his person. This requires that he actually believed such interference to be unlawful. The fact that his belief may have been erroneous does not deprive the defendant of his privilege to use force in defense of his person if a person of ordinary intelligence and prudence under the same circumstances would have believed such interference to be unlawful.
This jury instruction is Wis. J I — Crim. 800, and reflects language this court has previously approved. Crotteau v. Karlgaard, 48 Wis. 2d 245, 249-50, 179 N.W.2d 797 (1970) (citing 6 Am. Jur. 2d, Assault and Battery, p. 135, sec. 161) ("It is not necessary that the danger which gave rise to the belief actually existed; it is sufficient that the person resorting to self-defense at the time involved reasonably believed in the existence of such a danger, and such reasonable belief is sufficient even where it is mistaken.'1). See also Maichle v. Jonovic, 69 Wis. 2d 622, 628, 230 N.W.2d 789 (1975). The evidence which the *121defendant sought to have admitted into evidence may have convinced the jury that his testimony concerning Gregg's prior acts was accurate (if they were unconvinced previously). However, the test for self-defense is one of reasonableness, not of veracity. The question of whether his belief was erroneous was irrelevant. The important inquiry is not whether Daniels had good cause to hold such a belief (which is what the additional evidence would have addressed), but rather whether it is reasonable for a person in that situation to discharge three bullets into an unarmed man.
The additional evidence would not have informed the jury that Daniels had no opportunity to escape from Gregg or that Daniels and Brent could have not subdued Gregg without shooting him, nor would it have bolstered the reasonableness of Daniels' assertion that he was afraid of Gregg because of Gregg's prior conduct (see McMorris v. State, 58 Wis. 2d 144, 150, 205 N.W.2d 559 (1973)). Had the evidence been of this nature, it would have been relevant to the jury in determining whether Daniels' belief (erroneous or not) that shooting Gregg was necessary to avoid imminent death or great bodily harm, was reasonable under the circumstances. See sec. 939.48(1), Stats. Because the additional evidence did not go to the reasonableness of Daniels' belief, there is no reasonable possibility that the error (if there was one) contributed to the conviction. As such, the error was harmless. See State v. Dyess, 124 Wis. 2d 525, 543, 370 N.W.2d 222 (1985). For these reasons, I would reverse the court of appeals and would affirm the circuit court's decision to exclude this additional testimony as within his discretion. Accordingly, I dissent.
*122I am authorized to state that Justices Donald W. Steinmetz and Louis J. Ceci join in this dissenting opinion.
McCormick goes on to state: "when the identity of the first aggressor is really in doubt, the probative value of the evidence ordinarily justifies taking this risk." McCormick on Evidence, supra. The evidence before the circuit court overwhelmingly indicated that the victim was the first aggressor. Daniels, Reynolds and Brent (a witness at the preliminary hearing) testified that *118Gregg (the victim) was the first aggressor, and that Daniels had tried to calm him down. Gregg himself admitted that Daniels had attempted to calm him down before the shooting. Because of this, the probative value of the additional evidence would have been slight.