In this case, we consider whether the trial court prejudiced defendant Geraldine Lewis Ramos when it omitted the element of willfulness from jury instructions. Defendant was convicted of damaging a computer system at her workplace in violation of N.C.G.S. § 14-455, after being fired from her position at the Latin American Resource Center (“LARC”) in Raleigh. Because we conclude that the jury could reasonably have reached a different result but for this omission, we hold that the error was prejudicial, and we affirm the decision of the Court of Appeals granting defendant a new trial.
Defendant pleaded guilty to a misdemeanor violation of section 14-455 in District Court, Wake County. On 3 November 2005, she was sentenced to a term of forty-five days, suspended subject to supervised probation for twelve months. Defendant then appealed to superior court, where on 14 December 2006, a jury convicted her on the same charge. Judge Narley L. Cashwell sentenced defendant to a forty-five day term, but suspended the sentence subject to eighteen months of supervised probation.
Defendant appealed, and, in a divided opinion filed on 18 November 2008, the Court of Appeals ordered a new trial after concluding that there was a reasonable possibility that the verdict might have been different if the jury had been properly instructed. State v. Ramos, - N.C. App. -, -, 668 S.E.2d 357, 359 (2008). The entire panel agreed that the trial court failed to instruct on the element of willfulness, that the terms “willfully” and “without authorization” in the statute are not interchangeable, and that the proper standard of review is whether the instruction error prejudiced defendant. Id. at -, 668 S.E.2d at 362-63. However, the dissenter would find no prejudice because the evidence “unequivocally show[s] defendant’s actions in duplicating and removing the files was willful.” Id. at -, *354668 S.E.2d at 366 (Tyson, J., concurring in part and dissenting in part). This Court allowed the State’s motion for temporary stay and its petition for writ of supersedeas.
The evidence tended to show that defendant had worked as a community outreach coordinator at LARC since May 2005, supervised by Aura Camacho-Maas. One of defendant’s duties was writing grant proposals. In August 2005 Camacho-Maas informed defendant that she was being terminated after failing to timely complete two proposals. Camacho-Maas testified that defendant was enraged and crying and threatened to “destroy [Camacho-Maas] in the agency.” Defendant also refused to return her office key until she was paid. After terminating defendant, Camacho-Maas escorted defendant from LARC’s office and instructed the receptionist not to allow her back onto the premises. Shortly thereafter, Camacho-Maas found defendant and the receptionist removing defendant’s personal items from defendant’s LARC office, but said nothing. Later the same day, Camacho-Maas saw defendant and the receptionist again leaving defendant’s former office, and she became concerned. When Camacho-Maas checked defendant’s office computer, she discovered that certain important teacher apprenticeship program (“TAP”) files were missing from LARC’s server. Camacho-Maas testified that she knew the files had been on the server earlier that day before defendant’s termination and that only LARC employees could access the files. Camacho-Maas called the police, who investigated and confirmed that many LARC files had been deleted or overwritten.
On 16 August 2005, defendant returned to LARC, and CamachoMaas called police to the office. Defendant admitted that she had copied certain files onto her flash drive. At trial, defendant testified that she had told Camacho-Maas that she was going to delete various curriculum and grant proposal files and that Camacho-Maas had said she didn’t care whether defendant did so or not because defendant’s work was not good. Defendant denied having deleted any TAP files.
In pertinent part, section 14-455(a) states that “[i]t is unlawful to willfully and without authorization alter, damage, or destroy a computer, computer program, computer system, computer network, or any part thereof.” N.C.G.S. § 14-455(a) (2007) (emphasis added). Defendant requested an instruction that included the term “willfully” and its legal definition, but the trial court denied the request and instructed the jury as follows:
*355For you to find the defendant guilty of this offense, the State must prove two things:
First, that the defendant damaged a computer system or computer network or any part thereof by deleting a file or files from the computer system or computer network.
Second, that the defendant did so without authorization. A person is without authorization when although the person has the consent or permission of owner [sic] to access a computer system or computer network the person does so in a manner which exceeds the consent or permission.
If you find from the evidence beyond a reasonable doubt that on or about August the 15th, 2005 the defendant, without authorization, damaged a computer system or computer network, it would appeal [sic] your duty to return a verdict of guilty.
“[A] trial court must instruct the jury on every essential element of an offense . . . State v. Hunt, 339 N.C. 622, 649, 457 S.E.2d 276, 292 (1995). Section 14-455 requires that the alteration or damage to a computer be done “willfully.” “Willful” is defined as “the wrongful doing of an act without justification or excuse, or the commission of an act purposely and deliberately in violation of law.” State v. Arnold, 264 N.C. 348, 349, 141 S.E.2d 473, 474 (1965) (per curiam) (citations omitted). “Willfully” means “something more than an intention to commit the offense.” State v. Stephenson, 218 N.C. 258, 264, 10 S.E.2d 819, 823 (1940). Willfulness is an essential element which the fact-finder must determine, often by inference. Arnold, 264 N.C. at 349, 141 S.E.2d at 474.
As noted in both the majority opinion and the dissent at the Court of Appeals, failure to instruct on willfulness is subject to harmless error review. Ramos, - N.C. App. at -, -, 668 S.E.2d at 362, 364; see Arnold, 264 N.C. at 349, 141 S.E.2d at 474; State v. Rose, 53 N.C. App. 608, 611, 281 S.E.2d 404, 406 (1981); State v. Maxwell, 47 N.C. App. 658, 660, 267 S.E.2d 582, 584, appeal dismissed and disc, review denied, 301 N.C. 102, 273 S.E.2d 307 (1980). In such cases, we consider whether “there is a reasonable possibility that, had the error in question not been committed, a different result would have been reached at the trial out of which the appeal arises.” N.C.G.S. § 15A-1443(a) (2007). For example, in Rose, the Court of Appeals held that there could be no prejudice in convicting a defendant of felonious escape, an offense which includes the element of *356willfulness, when “nothing in the record in any way indicates that defendant’s escape was anything other than ‘willful.’ ” Rose, 53 N.C. App. at 611, 281 S.E.2d at 406 (emphasis added).
Here, defendant testified that she believed Camacho-Maas had authorized her to delete certain computer files which she had created at work. Defendant testified that Camacho-Maas told her that she could delete these files because “the work was not good, and it was [sic] no consequence.” Defendant further testified that CamachoMaas came into defendant’s office while she was deleting these very files and “didn’t say anything, but [Camacho-Maas] knew what I was doing.” Defendant also testified that she intentionally deleted only a few curriculum- and grant-related files that she considered personal and repeatedly stated that she did not delete any TAP files. Defendant also testified that, because the TAP files were located on LARC’s server, she did not believe she could access them while CamachoMaas had them open and did not think it was possible for her to have deleted the TAP files after her termination.
This is not a case with “nothing in the record” to support a conclusion of anything other than willfulness. Rose, 53 N.C. App. at 611, 281 S.E.2d at 406. Evaluating the credibility of defendant’s testimony in light of the other evidence was properly for the jury and the trial court’s instructional error prevented the jury from considering the willfulness of defendant’s actions. Based on defendant’s testimony, we conclude that there was a reasonable possibility that the jury could have found that defendant believed she had Camacho-Maas’ permission to delete all of the files that she intentionally deleted and that any deletion of the TAP files was accidental, not willful. Thus, the trial court’s failure to instruct on willfulness was not harmless. The Court of Appeals majority correctly granted defendant a new trial and we affirm.
AFFIRMED.
Chief Justice PARKER concurs in the result only.