(dissenting) — Under Vernon Clausing’s interpretation of the unlawful delivery statute, former RCW 69.41.030 (1994), anyone with access to a stash of legend drugs may lawfully hand those drugs over to anybody with a prescription. Presumably, then, any stock clerk at Rite Aid could pour pills into a pharmacy customer’s outstretched hand (or dump a quantity into a friend’s shopping bag) without committing an unlawful delivery of legend drugs. The majority swallows Clausing’s fishy interpretation hook, line, and sinker. To do so, it takes an entirely passive approach to reading former RCW 69.41.030. While it is one thing for a court to criticize the legislature for inelegant drafting, it is quite another to forgo reading a statute in light of the statutory definitions set forth just two sections prior. Application of the statutory definitions to the terms of art in a statute is essential to discerning the plain meaning of the statute. Dep’t of Ecology v. Campbell & Gwinn, L.L.C., 146 Wn.2d 1, 11, 43 P.3d 4 (2002) (concluding that plain meaning is derived “from all that the Legislature has said in the statute and related statutes which disclose legislative intent about the provision in question.”).
*631Because I conclude that the trial court looked intently at former RCW 69.41.030, interpreted its terms of art by applying the definitions in former RCW 69.41.010 (1994), and then properly instructed the jury on the meaning of unlawful delivery of legend drugs, I respectfully dissent.
A closer look at the genesis of Jury Instruction 17 is warranted. The starting point is former RCW 69.41.030:
It shall be unlawful for any person to sell, deliver, or possess any legend drug except upon the order or prescription of a physician under chapter 18.71 RCW, an osteopathic physician or an osteopathic physician and surgeon under chapter 18.57 RCW, . . . : PROVIDED, HOWEVER, That the above provisions shall not apply to . . . any practitioner acting within the scope of his or her license,....
Accordingly, the trial court instructed the jury that “ [i] t is a crime for any person to deliver a legend drug except upon the order or prescription of a licensed physician or osteopathic physician except as authorized by law.”3 The court thus gave the following “to convict” instruction:
To convict the defendant, Vernon Clausing, of the crime of unlawful delivery of a legend drug as charged in Count I, each of the following elements of the crime must be proved beyond a reasonable doubt:
(1) That on or about the 27th day of July, 1995, Vernon Clausing unlawfully delivered a legend drug; and
(2) That the acts occurred in the State of Washington.
If you find from the evidence that each of these elements has been proved beyond a reasonable doubt, then it will be your duty to return a verdict of guilty as to Count I.
On the other hand, if, after weighing all the evidence, you have a reasonable doubt as to any one of these elements, then *632it will be your duty to return a verdict of not guilty as to Count I_[4]
But plainly, this instruction, which tracks the pattern jury instruction, does nothing to define the crime of unlawful delivery. See 11 Washington Pattern Jury Instructions: Criminal 55.04, at 694 (2d ed. 1994) (WPIC). Here, the first “element” of the crime of “unlawful delivery of a legend drug” is proof beyond a reasonable doubt that the defendant “unlawfully delivered a legend drug.”5
To clarify the circular first element of the “to convict” instruction, the trial court turned to WPIC 55.06:
It is not unlawful to deliver a legend drug upon the order or prescription of a physician.
The State has the burden of proving beyond a reasonable doubt that the defendant did not deliver a legend drug upon the order or prescription of a physician.
But this pattern instruction has the same limitation as the “to convict” instruction—it says nothing new or enlightening. The instruction merely transforms the statute’s positive statement (already set forth in instruction 7) into a negative one and reiterates that the State has the burden of proof, a fact the court had made plain in instruction 6. See Clerk’s Papers (CP) at 199. Nevertheless, Clausing’s advisory attorney proposed WPIC 55.06 virtually verbatim, see CP at 163, and Clausing himself proposed only a slightly expanded version: “It is not unlawful for an unlicensed person to possess or deliver a legend drug upon an order or prescription from a licensed physician in the line of his legitimate employment.” CP at 182.
*633Faced with pattern jury instructions saying little more than that an unlawful delivery requires proof of an unlawful delivery and that a lawful delivery is not an unlawful delivery, the trial court modified WPIC 55.06 to set forth for the jury just what constitutes a lawful delivery and what precisely the State must prove:
It is not unlawful to deliver a legend drug if the legend drug either: 1) is dispensed by a licensed practitioner upon the order or prescription of a licensed physician or osteopathic physician; or 2) is delivered by a practitioner acting within the scope of his or her license.
The State has the burden of proving beyond a reasonable doubt that the legend drugs in Counts I, II, and III were not dispensed by a licensed practitioner upon the order or prescription of a licensed physician and that they were not delivered by a practitioner acting within the scope of his or her license.
CP at 210 (Jury Instruction 17). Responding to Clausing’s objection, the trial court emphasized the necessity of this instruction: “If I were to take [instruction 17] out altogether, there would [be] no guidance to the jury on the issue of what is lawful or unlawful, . . . .” Report of Proceedings (RP) (Mar. 2, 1998) at 24.
This jury instruction adeptly synthesizes former RCW 69.41.030 and the definitions in section .010 of key terms used in section .030. The statutory definition of “legend drugs” is essential to understanding what constitutes an unlawful delivery of legend drugs under RCW 69.41.030: “ ‘Legend drugs’ means any drugs which are required by state law or regulation of the state board of pharmacy to be dispensed on prescription only or are restricted to use by practitioners only” Former RCW 69.41.010(9) (emphasis added). The trial judge thus observed that the statutory definition of “legend drugs” required that such drugs “either be dispensed on prescription or . . . used by a practitioner in the scope of their license.” RP (Mar. 2,1998) at 16. The word “dispensed” is also a term of art with a statutory definition: “ ‘Dispense’ means the interpretation of a prescription or order for a legend drug and, pursuant to that prescription *634or order, the proper selection, measuring, compounding, labeling, or packaging necessary to prepare that prescription or order for delivery.” Former RCW 69.41.010(4). The statute defines a “dispenser” as “a practitioner who dispenses” and, in turn, defines a “practitioner” as inter alia a licensed physician, a licensed osteopathic physician or surgeon, or a pharmacy licensed to dispense legend drugs. Former RCW 69.41.010(5), (11). Thus, the statutory definition of “legend drugs,” read in the light of the definition of “dispense,” establishes that legend drugs either must be prepared by a practitioner (that is, by a licensed physician or pharmacy) on prescription only or must be used by a licensed physician.
These requirements are reinforced in the statutory definition of “deliver”: “ ‘Deliver’ or ‘delivery’ means the actual, constructive, or attempted transfer from one person to another of a legend drug, whether or not there is an agency relationship.” Id. at subsection (2) (emphasis added). Further insight into the meaning of “deliver” is afforded in the contrasting definition of “distribute”: “ ‘Distribute’means to deliver other than by administering or dispensing a legend drug.” Id. at subsection (6) (emphasis added). That delivery of a legend drug is here equated with either “dispensing” or “administering” the legend drug reinforces the definition of “legend drugs” as drugs that must be either dispensed by a practitioner upon a valid prescription or used by a practitioner.
In sum, former RCW 69.41.030, interpreted in accord with the relevant definitions in section .010, establishes that a licensed physician may permissibly use or administer legend drugs and that, where a physician instead writes the patient a prescription, another practitioner (that is, another licensed physician or pharmacy) must assume responsibility for dispensing that drug—by interpreting the prescription and carrying out any necessary tasks of selecting, labeling, or packaging the drug for delivery. Former RCW 69.41.010(4). The trial court thus correctly instructed the jury that a legend drug is lawfully delivered if it “1) is *635dispensed by a licensed practitioner upon the order or prescription of a licensed physician or osteopathic physician; or 2) is delivered by a practitioner acting within the scope of his or her license.” CP at 210 (Jury Instruction 17).
Clausing’s initial criticism of Jury Instruction 17 betrays his entirely erroneous assumption that he was entitled to dispense legend drugs. He described the instruction as “a little garbled, because it isn’t the physician who dispenses it. It is his employees, see?” RP (Mar. 2, 1998) at 21. Thus, in Clausing’s account of the transaction, he was merely functioning as an employee handing the legend drugs to the patient, but this convenient view eliminates the crucial intermediate step between the presentation of the prescription and the ultimate act of transferring the legend drugs to the patient. Clausing plainly does not accept that legend drugs must be dispensed by a practitioner (that is, by a licensed physician or pharmacy) before any unlicensed employee of that practitioner may legitimately transfer the legend drugs to the patient. Clausing has to express that belief because the facts unequivocally establish that he took pills from his stock of “bootleg rum,” as he called it, and turned them over in plastic sandwich baggies to Sheryl Reynaga, a former patient working as a police agent. Ex. 9, at 34; see also RP (Feb. 3, 1998) at 32, 37. The majority’s extraordinary unwillingness to apply to former RCW 69-.41.030 the statutory definitions of section .010 licenses Clausing’s self-serving misperception that a legend drug need not be dispensed by a practitioner. The majority’s acceptance of Clausing’s simplistic, distorted interpretation of the statute compares poorly to the conscientious efforts of the trial judge. I agree with the Court of Appeals that the trial court properly instructed the jury on the unlawful delivery of legend drugs.
I also agree with the conclusion of the Court of Appeals that any error in the trial court’s admission of expert opinion testimony under ER 401 was harmless. An evidentiary error requires reversal if it results in prejudice— that is, if it can be reasonably said that “the outcome of the *636trial would have been materially affected had the error not occurred.” State v. Tharp, 96 Wn.2d 591, 599, 637 P.2d 961 (1981); see also State v. Bourgeois, 133 Wn.2d 389, 403, 945 P.2d 1120 (1997). The State called Donald Williams, the executive director of the Washington State Board of Pharmacy, and asked him whether a prescription written by a doctor whose license is revoked the following day would be a valid prescription. Clausing objected, the jury was excused, and the matter discussed; the trial court then instructed the jury that Williams’s “answers should not be considered by you as a legal opinion—an opinion as to what the law is or what the law is that you would apply in this case.” RP (Feb. 11, 1998) at 15; see State v. Hanna, 123 Wn.2d 704, 711, 871 P.2d 135 (1994) (stating that “|j]uries are presumed to heed the court’s instructions.”). Williams then expressed his belief that preexisting prescriptions of a doctor whose license is revoked are no longer valid and may not be refilled.
I agree with the Court of Appeals that the opinion testimony served no relevant purpose “because Clausing never introduced any prescriptions or medical records to corroborate his claim of preexisting authority” for the prescriptions. State v. Clausing, 104 Wn. App. 75, 87, 15 P.3d 203 (2001). More importantly, the presentation of this irrelevant testimony did not prejudice Clausing. The validity of Sheryl Reynaga’s allegedly preexisting prescriptions was irrelevant to the outcome of the trial because, as discussed above, Clausing’s delivery of the legend drugs was unlawful on other grounds: he was not delivering the drugs as a licensed physician, nor was he delivering drugs that had been previously dispensed by a licensed physician or pharmacy. In light of the curative instruction and Clausing’s failure to show prejudice, this court should affirm the conclusion of the Court of Appeals that any error here was harmless.
Similarly, Clausing’s claim of prosecutorial misconduct is unavailing. To prevail on a claim of prosecutorial misconduct, a defendant bears the burden of showing that the *637prosecutor’s comments were improper and that there is a substantial likelihood that the comments affected the jury’s decision. State v. Reed, 102 Wn.2d 140, 145, 684 P.2d 699 (1984); State v. Russell, 125 Wn.2d 24, 85, 882 P.2d 747 (1994). In closing argument, the prosecutor told the jury that “[t]he head of the Board of Pharmacy, the man who in this station is responsible for the regulations of these drugs [,] says, ‘When you lose your license to practice medicine, your prescriptions are void.’ ” RP (Mar. 2, 1998) at 101. The trial court sustained Clausing’s objection that the prosecutor’s remark misstated the facts. However, the court overruled a subsequent objection when the prosecutor went on to say that “[t]he fact remains there was no valid prescription in this case.” Id. at 101-02. As to this second statement, the Court of Appeals correctly observed that the prosecutor had fairly characterized the facts, given that no prescriptions were placed in evidence. Clausing, 104 Wn. App. at 87. Regarding the prosecutor’s first comment, Clausing cannot show that there was a substantial likelihood that the comment affected the jury’s decision; the trial court sustained Clausing’s objection, and for the same reasons that the expert opinion testimony was not prejudicial, the allusion to that testimony in closing argument did not constitute prejudicial prosecutorial misconduct.
In sum, I would affirm the decision of the Court of Appeals on all points. The Court of Appeals correctly concluded that the jury instructions had not misstated the law regarding the unlawful delivery of a legend drug, that any error in the admission of opinion testimony had been harmless, and that Clausing had not shown prejudicial prosecutorial misconduct.
Johnson and Madsen, JJ., concur with Owens, J.
Clerk’s Papers (CP) at 200 (Jury Instruction 7). This instruction inserts the word “licensed” into the pattern jury instruction, an addition comporting with the statute’s citation of the licensing statutes. See 11 Washington Pattern Jury Instructions: Criminai, 55.03, at 693 (2d ed. 1994). Clausing’s proposed instruction likewise inserts the word “licensed.” CP at 181.
CP at 207 (Jury Instruction 14). Por counts II and III, the court gave the same instruction, changing only the count number and the applicable date. Id. at 208-09 (Jury Instructions 15-16).
Clausing’s advisory attorney submitted this instruction, but Clausing subsequently proposed that the first element be expanded with the phrase “to a person without a prescription or order from a licensed physician”; he then made the handwritten alteration “to a person for whom their [sic] was no prescription on record.” CP at 183.