(dissenting)
¶31 Anthony Clark was convicted of first degree murder of his friend, D.D.9 The State argued that Clark shot D.D. with premeditated intent to kill in the course of stealing D.D.’s drugs; Clark admitted that he shot D.D., but claimed that it was an accident because he thought the gun was not loaded. Thus, the only question at trial was Clark’s mental state. The trial court therefore permitted the State to present substantial evidence regarding Clark’s premeditated intent. And the trial court ultimately instructed the jury on several lesser included offenses—intentional second degree murder, reckless first degree manslaughter, and negligent second degree manslaughter—all defined by mental states less culpable than premeditation.10 But it barred Clark from presenting most of his proffered evidence refuting premeditated intent. Most critically, it excluded expert testimony about Clark’s intellectual disabilities that could have bolstered his accident defense, reasoning that such testimony is inadmissible unless the defendant pleads diminished capacity.
*657¶32 The majority approves this distinction between lay and expert testimony. It holds that lay “observation testimony” regarding Clark’s intellectual disabilities was relevant to rebut the element of mens rea even though Clark did not plead a diminished capacity defense, but it reaches the opposite conclusion about expert testimony on Clark’s disability. Majority at 649-50 (“The court . . . properly allowed relevant observation testimony tending to rebut the State’s mens rea evidence and properly excluded expert testimony that was not relevant absent a diminished capacity defense.”). Thus, the majority holds that the strongest evidence of Clark’s intellectual disabilities—a psychologist’s testimony that Clark had developmental disabilities, exceedingly low intelligence quotient (IQ) scores, and a diagnosis of mild mental retardation—was inadmissible to support the defense’s accident and/or lesser included offense theories. 2 Verbatim Report of Proceedings (VRP) (3.5 Hr’g) (Oct. 4, 2012) at 268-74, 314, 283.
¶33 This distinction is illogical and violates the constitutional right to present a defense. I respectfully dissent.
I. The Trial Court Admitted Certain Lay Observation Testimony Supporting the Defense, but Excluded the More Neutral, More Persuasive Medical Expert Testimony Supporting the Same Defense Theory
¶34 Clark testified that on the morning of the shooting, he was walking from his apartment to a neighborhood barbecue when he saw D.D.—an acquaintance from school—standing at a crosswalk. The two talked briefly, and Clark then invited D.D. over to his apartment.
¶35 At the apartment, D.D. opened his coat pocket and showed Clark a .22 caliber gun and an M&M’s container filled with pieces of crack cocaine, and then asked Clark to help him sell the drugs. Clark testified that he went upstairs to ask his neighbors to buy the drugs, but they declined, so Clark came back downstairs and suggested that he and D.D. pawn his mother’s gold necklace for money instead.
*658¶36 According to Clark, the necklace was in a jewelry box on the top shelf of a bedroom closet. Clark tried but failed to reach the box, so D.D. decided to try. He told Clark to move out of his way. Before climbing up to reach for the box, though, D.D. disarmed: he pulled the .22 caliber gun out of his coat pocket, removed the magazine, and handed the gun without the magazine to Clark. D.D. kept the magazine. Clark testified that as D.D. reached into the closet, still holding that magazine, Clark sat on the floor and played with the gun. Thinking the gun was unloaded because the magazine was out,11 Clark aimed it at the ceiling of the closet and pulled the trigger. The bullet struck D.D. in the back of his head.
¶37 Clark claimed that he then tried to resuscitate D.D. 13 VRP (Apr. 15, 2013) at 1658-59, 1663. He did one compression. Id. at 1663. He then put the magazine back into the gun and hid both the gun and the drugs inside his toilet. Id. at 1672-73. (That’s where officers later found them.) Clark then went upstairs to ask his neighbors for help disposing of a body. He testified that he was crying and shaking at the time. Id. at 1666, 1669. As discussed below, that contradicted his neighbors’ testimony that Clark was oddly calm when talking about the body.
¶38 The prosecution argued that Clark was a sophisticated killer, too familiar with guns to have thought that D.D.’s gun was unloaded just because the magazine had been removed. 14 VRP (Apr. 16, 2013) at 1764-65. To support that theory, the State offered testimony by three of Clark’s neighbors regarding conversations that they had with Clark on the day of the shooting. These neighbors all agreed that Clark asked them to buy or help sell crack cocaine first, and then later asked them to help him dispose of a body. Specifically, they all testified that Clark told them *659that a friend had given him the cocaine to sell so that he could buy school clothes—even though Clark was no longer in school. 8 VRP (Mar. 19, 2013) at 848, 854, 904-05; 9 VRP (Mar. 20, 2013) at 1002-07, 1026-27. Some said that Clark then left and came back to talk about the body; others said that Clark stayed and talked about the body. 8 VRP (Mar. 19,2013) at 850-53; 9 VRP (Mar. 20,2013) at 1007-08,1032. Two neighbors testified that Clark said he “popped” the person in the head with a “deuce deuce.” 8 VRP (Mar. 19, 2013) at 851, 853, 907. All three neighbors recounted that Clark said he did that because that person was hitting “his baby’s mom” and that he was taught never to let anyone harm his baby’s mom—even though Clark had no children. Id. at 850; 9 VRP (Mar. 20, 2013) at 1035. Despite Clark’s confession, the neighbors remained unsure whether Clark was joking, partly because of his oddly calm demeanor and partly because he sometimes said he was joking. 8 VRP (Mar. 19, 2013) at 850-51, 863-64, 894, 906-07, 912; 9 VRP (Mar. 20, 2013) at 1010. But Clark eventually took one neighbor to the garbage can behind their apartment building and showed her D.D.’s hidden body. 8 VRP (Mar. 19, 2013) at 863-66, 894, 912; 9 VRP (Mar. 20, 2013) at 1012.
¶39 The trial court did permit Clark to present lay testimony that he was in high school “beyond normal age” and attended special education classes. VRP (Dec. 17, 2012) at 20-21. As discussed further below, though, the trial court excluded the bulk of the defense-proffered evidence on Clark’s diagnoses of “mild mental retardation”—evidence from a neutral expert witness. 2 VRP (3.5 Hr’g) (Oct. 4, 2012) at 314. On the basis of the testimony about learning problems alone, though, the defense argued—apparently not persuasively—that Clark had below average intelligence and simply mishandled the gun:
Would I characterize Anthony as a man? No. You’re talking about, at the time, a 20 year old who had just graduated from special education. . . .
*660
... As far as he knew at the time, the bullets had been removed from the gun ... which is probably exactly what [D.D.] thought when he handed that to Anthony. And he probably did that knowing that Anthony’s not your average 20 year old.
15 VRP (Apr. 17, 2013) at 1816, 1826 (emphasis added).
¶40 The defense sought to bolster the lay testimony supporting its accident theory with the far more persuasive testimony of Dr. Brent Oneal, a psychologist who personally evaluated Clark and diagnosed him with “mild retardation.” 2 VRP (3.5 Hr’g) (Oct. 4, 2012) at 260, 314. The State acknowledged that this testimony tended to rebut the element of mens rea, but moved to exclude the testimony anyway, arguing that it would be too confusing for jurors in the absence of a diminished capacity defense:
[T]he jurors would likely be confused about how to evaluate [Dr. Oneal’s] evidence. They would wonder whether a “mentally retarded” person is able to form a specific intent like a person of normal intelligence. Such confusion is both needless and patently unfair to the State where the defense has not raised a diminished capacity defense.
Clerk’s Papers (CP) at 218. The defense responded that Dr. Oneal’s testimony was also relevant to “support a finding of recklessness or criminal negligence” as opposed to premeditated intent because the diagnosis and associated explanation made it less likely that Clark knew or understood the risks posed by firing the gun. CP at 225.
¶41 The trial court agreed with the State. It allowed certain lay testimony regarding Clark’s intellectual deficits and gave lesser included offense instructions on manslaughter (reckless and negligent), but it excluded Dr. Oneal’s more educated, more neutral medical testimony on the same point as unduly confusing in the absence of a diminished capacity defense.
*661II. The Majority Approves This Distinction between Lay and Expert Testimony Because It Erroneously Equates All Expert Testimony about Intellectual Deficits with a Diminished Capacity Defense
¶42 “Diminished capacity is a mental condition not amounting to insanity which prevents the defendant from possessing the requisite mental state necessary to commit the crime charged.” State v. Furman, 122 Wn.2d 440, 454, 858 P.2d 1092 (1993) (citing State v. Ferrick, 81 Wn.2d 942, 944, 506 P.2d 860 (1973)). The majority is correct that in order to assert a diminished capacity defense, a defendant must meet two threshold criteria: (1) the defendant must present “substantial evidence of such a condition” and (2) “the evidence must logically and reasonably connect the defendant’s alleged mental condition with the asserted inability to form the required specific intent to commit the crime charged.” Ferrick, 81 Wn.2d at 944-45; State v. Griffin, 100 Wn.2d 417, 419, 670 P.2d 265 (1983).
¶43 If Clark had offered Dr. Oneal’s testimony as evidence that he lacked the capacity or ability to act intentionally when he shot D.D., then I might agree with the majority that it was properly excluded. The reason is that Dr. Oneal did not testify that Clark was incapable of intentionally shooting D.D., and thus his testimony would likely not satisfy the second prerequisite to asserting a diminished capacity defense. But, as explained above, Clark did not offer Dr. Oneal’s testimony to establish a diminished capacity defense—he offered it to bolster his accident theory. In other words, Clark never argued that he was incapable of shooting D.D. intentionally; he argued that he did not in fact intend to shoot him.
¶44 The majority fails to appreciate this distinction. Relying on State v. Atsbeha, 142 Wn.2d 904, 918, 16 P.3d 626 (2001) and State v. Greene, 139 Wn.2d 64, 73-74, 984 P.2d 1024 (1999), the majority concludes that expert testimony—i.e., a “clinical[ ] evaluation]”—advances a dimin*662ished capacity defense any time it shows that “intellectual deficits impaired [a defendant’s] ability to understand and assess the risks of his behavior, thereby reducing the likelihood that [he] acted with a culpable mental state.” Majority at 651. But neither case stands for this principle. Atsbeha addressed expert testimony that the defendant could intentionally deliver drugs but harbored a delusion that he was cooperating in a sting operation with the undercover officer who asked him to make the delivery. 142 Wn.2d at 907-08, 910-11. It held that this testimony was relevant to an insanity defense, but not to a diminished capacity defense (because it did not negate specific intent). Id. at 920. And Greene held that testimony regarding the defendant’s dissociative identity disorder (DID) was properly excluded as unhelpful because, given the state of the relevant science at the time, “it was not possible to reliably connect the symptoms of DID to the sanity or mental capacity of the defendant.” 139 Wn.2d at 79. These cases are straightforward applications of our Evidence Rules in the context of insanity and diminished capacity pleas. They do not limit the other purposes for which a defendant might admit expert testimony on his cognitive abilities. In other words, diminished capacity evidence is a subset of evidence concerning cognition and mens rea. But cognition and mens rea are far bigger categories.
III. By Excluding Defense Evidence That Could Rebut the State’s Evidence on the Element of Mens Rea, the Trial Court Violated Clark’s Constitutional Right To Present a Defense
¶45 “Few rights are more fundamental than that of an accused to present witnesses in his own defense.” Chambers v. Mississippi, 410 U.S. 284, 302, 93 S. Ct. 1038, 35 L. Ed. 2d 297 (1973). That right is based on the right to due process of law (U.S. Const, amend. XIV; Const, art. I, § 3) and the rights of an accused in a criminal proceeding (U.S. Const, amend. VI; Const, art. I, § 22). State v. Jones, 168 Wn.2d 713, 720, *663230 P.3d 576 (2010) (“ ‘The right of an accused in a criminal trial to due process is, in essence, the right to a fair opportunity to defend against the State’s accusations.’ ” (quoting Chambers, 410 U.S. at 294)).
¶46 To be sure, this right to present evidence extends only to relevant evidence. State v. Hudlow, 99 Wn.2d 1, 16, 659 P.2d 514 (1983). But evidence is relevant if it tends to make more or less probable the existence of any fact that is of consequence to the outcome. ER 401. In this case, the trial court concluded that Dr. Oneal’s testimony was not relevant unless it was offered to support a diminished capacity defense. The majority affirms because it concludes that Clark really was advancing such a defense, even though he did not formally plead it—indeed, Clark specifically denied it.
¶47 For the reasons given in Part II above, I disagree with that conclusion; Clark’s accident defense was not the same thing as a diminished capacity defense. Thus, this case requires us to answer the following question: Where a defendant offers expert testimony regarding his or her intellectual deficits to rebut the State’s theory of motive or intent, do the prerequisites to the presentation of a diminished capacity defense still apply?
¶48 This is a question of first impression in Washington, but the New Jersey Supreme Court has addressed it. In State v. Burr, the State charged Burr, a piano teacher, with sexual assault and endangering the welfare of a child based on allegations that he had fondled one of his students. 195 N.J. 119, 122, 948 A.2d 627 (2008). As proof of Burr’s sexual deviance, the State presented evidence that Burr would often allow his students to sit on his lap. Id. at 125. To rebut the resulting inference that he was intentionally grooming these students for sexual abuse, Burr offered evidence that he suffered from Asperger’s syndrome and that as a result of this condition, he had a limited understanding of what constitutes basic and appropriate social interactions between adults and children. Id. at 129. He also offered that *664evidence to assist the jury in assessing his unusual demeanor at trial. Id. The trial court excluded this evidence, ruling that such evidence was admissible only to support a diminished capacity defense, which Burr was not seeking. Id. The New Jersey Supreme Court reversed, explaining that even though Burr was not seeking a diminished capacity defense, evidence of this condition remained relevant and therefore should have been admitted to support his claim of innocence. Id. at 129-30. As the court explained, evidence of Burr’s developmental condition was so highly relevant and significant to his claim of innocence that it “deified] specific enumeration.” Id. at 130.
¶49 Evidence of Clark’s substantial intellectual deficits and mild mental retardation diagnosis was equally relevant and significant to his argument that D.D.’s death was an accident or, alternatively, that it was not premeditated or intentional. To convict Clark of first degree murder, the State had to prove premeditated intent beyond a reasonable doubt. All Clark needed to do was cast doubt on the State’s evidence of premeditated intent. He could also show that the homicide was an accident (and not premeditated or intentional or reckless). Clark tried to do both by testifying that he believed the gun was unloaded at the time of the shooting and that he did not recognize the substantial risk involved in pulling the trigger without first checking the chamber for a bullet. The defense focused on Clark’s poor reasoning abilities. Evidence that he was mentally retarded with an exceedingly low IQ score (scoring in the bottom first and second percentile of others his age in perceptional reasoning, working memory, and verbal comprehension) was certainly relevant to his claim. Evidence of Clark’s mental process was also relevant because it rebutted the State’s evidence of premeditated intent. See State v. Sexton, 311 N.J. Super. 70, 88, 709 A.2d 288 (1998) (holding in an analogous shooting case that evidence of the defendant’s limited mental ability and his status as a special education student was relevant to his credibility about whether he *665actually believed the gun was unloaded and whether he acted recklessly), aff’d on other grounds, 160 N.J. 93, 733 A.2d 1125 (1999).
¶50 Thus, I would hold that the trial court erred by excluding expert testimony about Clark’s intellectual deficits as irrelevant in the absence of a diminished capacity defense.12 Jones, 168 Wn.2d at 720-21 (exclusion of defense-proffered evidence that effectively precludes a criminal defendant entirely from being able to present his version of the events or establishing his innocence violates his or her right to present a defense). Based on the analysis above, the evidence was highly relevant and its exclusion violated not just the Rules of Evidence but also the right to present a defense.
IV. The Exclusion of Expert Testimony on Clark’s Mild Mental Retardation Was Not Harmless Error
¶51 A trial court’s decision to exclude defense evidence in a criminal trial is generally subject to harmless error analysis under the “ ‘ “overwhelming untainted evidence” test.’ ” State v. Lord, 161 Wn.2d 276, 295, 165 P.3d 1251 (2007) (quoting State v. Smith, 148 Wn.2d 122, 139, 59 P.3d 74 (2002) (citing State v. Guloy, 104 Wn.2d 412, 426, 705 P.2d 1182 (1985))). Under that test, error is harmless if the untainted, admitted evidence is so overwhelming as to necessarily lead to a finding of guilt. Id. at 296. “[E]rror is not prejudicial if the evidence is of minor significance when compared to the overall weight of the evidence.” Id. (citing *666State v. Bourgeois, 133 Wn.2d 389, 403, 945 P.2d 1120 (1997)). Where, as here, the error is of constitutional magnitude, however, the error is deemed harmless only if the State proves “beyond a reasonable doubt that any reasonable jury would have reached the same result without the error.” Smith, 148 Wn.2d at 139 (citing State v. Whelchel, 115 Wn.2d 708, 728, 801 P.2d 948 (1990)).
¶52 At trial, the State’s theory was that Clark lured D.D. to his apartment to kill him and steal his drugs. Clark denied that he premeditated or intended the killing because he thought the gun was not loaded. Clark also denied that he acted recklessly, claiming that he did not recognize the substantial risk involved in pointing a gun that he believed was unloaded at someone and then pulling the trigger without first checking to see if a bullet was chambered.
¶53 The State presented evidence in support of its theory that showed that Clark had at least some knowledge about guns (or gun rhetoric). He referred to the .22 caliber gun as a “deuce deuce,” called the magazine a “clip,” acknowledged that guns were dangerous, admitted that he thought the particular gun was capable of shooting a bullet, and was able to insert the magazine back into the gun before hiding it in his toilet. The jury also heard that Clark had graduated from high school,13 that he confessed to shooting D.D. because D.D. had struck his fictitious “baby’s mom,” and that Clark was strangely calm during that confession.
¶54 To rebut the State’s evidence that he was a cold, calculated killer, Clark offered lay and expert testimony about how he was slow and did not process information the way other people his age did. But the trial court excluded most of it. It barred all testimony from Dr. Oneal about Clark’s substantial intellectual deficits.14 Dr. Oneal would *667have testified, based on his personal testing and evaluation of Clark, that Clark was born prematurely and with significant developmental delays; was highly suggestible and therefore prone to change his story when pressured; and had a very low IQ score, indicating that he had extremely poor perceptional reasoning, working memory, and verbal comprehension skills compared to others his age. 2 VRP (3.5 Hr’g) (Oct. 4, 2012) at 268, 271-74, 283.
¶55 The only evidence the trial court clearly permitted the jury to hear about Clark’s intellectual deficits was that he was enrolled in special education with an individualized education plan (but not how long or why he was on it), that neighbors thought he was slow (but not the expert testing to show exactly how slow he really was), and that he was on Social Security disability (but not that he was on it because of his mild mental retardation diagnosis).15 In essence, the trial court excluded the most neutral, educated, and meaningful evidence about Clark’s intellectual deficits.
¶56 The only real issue in this case was intent. The trial court excluded proffered defense evidence that was directly relevant to mens rea and that rebutted the State’s evidence of premeditation. The error might well have affected the outcome. We are especially certain of this given the fact that the trial court felt that there was sufficient evidence of mental states less culpable than premeditation to support jury instructions on intentional, reckless, and negligent homicide. CP at 288-95.1 would therefore conclude that the trial court’s error was not harmless under either the evi-dentiary or constitutional standards.
*668CONCLUSION
¶57 The trial court improperly excluded evidence of Clark’s intellectual deficits in violation of the Evidence Rules and Clark’s constitutional right to present a defense. This error was not harmless. I therefore respectfully dissent.
Fairhurst, C.J., and Madsen and Owens, JJ., concur with Gordon McCloud, J.D.D. was a minor at the time—initials are used to protect the minor’s privacy.
See State v. Jones, 95 Wn.2d 616, 621-22, 628 P.2d 472 (1981) (recklessness and negligence are lesser mental states “included” in intent; defendant charged with intentional murder was entitled to manslaughter instruction where evidence of intoxication supported theory that killing was unintentional); State v. Condon, 182 Wn.2d 307, 319, 343 P.3d 357 (2015) (intentional murder is lesser included offense in premeditated murder).
Although Clark said that he thought the gun was unloaded at the time he pulled the trigger, he also testified that he knew that guns were dangerous and that he thought the gun was capable of firing a bullet at some point in time. 13 VRP (Apr. 15, 2013) at 1595, 1660 (“Q. Did you, at any time[,] think[ ] that you could fire a bullet out of that gun? A. Yes. Q. Did you think it was loaded? A. No.”).
The United States Supreme Court has held that where state evidentiary rules bar evidence of a defendant’s diminished capacity to form the requisite mens rea as irrelevant absent a full-fledged insanity defense, then that state court can exclude such evidence under its state evidentiary rules without violating the federal right to present a defense. Clark v. Arizona, 548 U.S. 735, 760-79, 126 S. Ct. 2709, 165 L. Ed. 2d 842 (2006). But our state laws make such evidence relevant and admissible where, as here, they bear on the defendant’s mens rea and rebut the State’s evidence of mens rea. The Supreme Court’s holding in Clark is therefore inapplicable here. See id. at 772-78 (concluding that if a State has such a rule barring a defendant’s mental disease and incapacity evidence, then that rule might be a sufficiently “good reason’’ to satisfy federal due process requirements). This is likely the reason that neither party cited it.
The jury was not informed that Clark had not technically graduated from high school; he only aged out.
The trial court also barred certain lay testimony from Clark’s mother on this same topic. She would have confirmed that he had been in special education since *667he was four years old, that his so-called friends would take advantage of him because of his limitations, and that he could not drive because he could not pass the driver’s license exam despite several attempts. 11 VRP (Mar. 26, 2013) at 1373-74.
It was unclear from the court’s different rulings whether it would have allowed Clark to testify about the reason he was on Social Security disability (i.e., because of his mild mental retardation diagnosis). 7 VRP (Mar. 18, 2013) at 660-63.