¶1 Brian Long appeals the denial of his motion for a new trial based on a claim of juror misconduct. The question before us is whether the juror declarations Long submitted in support of his motion describe actual misconduct by jurors or instead reveal matters that inhere in the verdict. We conclude the declarations expose the jury’s deliberative process behind closed doors and cannot be considered to impeach the verdict. Accordingly, we affirm the trial court and the Court of Appeals’ conclusion that Long is not entitled to a new trial.
*130FACTS AND PROCEDURAL HISTORY
¶2 Long sued his former employer, Bo Brusco and Brusco Tug & Barge Inc. (Brusco), alleging wrongful termination in retaliation for opposing Brusco’s discriminatory conduct against another employee. The underlying facts were hotly disputed and centered on Brusco’s response to Long’s having hired as a deckhand Anthony Morgan, an individual who had a prosthetic leg. Morgan was not a party to this lawsuit. As Judge William Downing explained in his order denying Long’s motion for a new trial, “It was repeatedly conveyed to the jury that whether or not, in hindsight, Mr. Morgan was discriminated against was not their concern; rather, their focus should begin with the question of whether or not Mr. Long, at that time, had a reasonable belief that Mr. Morgan was being discriminated against.” Clerk’s Papers (CP) at 1948.
¶3 The reasonable belief element of Long’s claim was not strongly disputed. Indeed, Brusco conceded that Long reasonably believed Morgan was discriminated against. 19 Verbatim Report of Proceedings (VRP) (May 7, 2013) at 2329-30. “The elements that developed as constituting the crux of the jury’s work were (a) whether the plaintiff engaged in opposition conduct (or did his support for Mr. Morgan cease once the discriminatory act was done?), (b) whether the plaintiff suffered an adverse employment action (or was he given a lateral transfer to a higher paying position?), and (c) whether any such adverse employment action was taken with a retaliatory motive (or was it because of his missing a ship assist job?).” CP at 1949. To establish his claim, Long needed to prevail at trial on all of these disputed issues.
¶4 Following a two-week trial and at the end of two days of deliberations, the jury returned a verdict in favor of Brusco, by a vote of 10-2. Long’s attorneys thereafter interviewed jurors who were willing to talk and secured *131declarations from 4 of the 12. In support of his motion for a new trial, Long submitted the 4 jurors’ declarations, which address various aspects of the trial and deliberations. CP at 1768-79, 1780-92.1
¶5 The trial court denied Long’s motion, and the Court of Appeals affirmed in an unpublished opinion. Long v. Brusco, No. 70529-6-I, slip op. at 16 (Wash. Ct. App. Aug. 11, 2014) (unpublished), http://www.courts.wa.gov/opinions/pdf/705296.pdf. We granted Long’s petition for review. 182 Wn.2d 1021, 345 P.3d 785 (2015).
ANALYSIS
¶6 Central to our jury system is the secrecy of jury deliberations. Courts are appropriately forbidden from receiving information to impeach a verdict based on revealing the details of the jury’s deliberations. Thus, in considering whether to declare a mistrial based on alleged juror misconduct, the first question is whether the facts alleged “inhere! ] in the verdict”; this is a question of law we review de novo. Ayers v. Johnson & Johnson Baby Prods. Co., 117 Wn.2d 747, 768, 818 P.2d 1337 (1991).
¶7 Our case law recognizes two tests for determining whether facts in a juror declaration inhere in the verdict. Under the first test, facts “linked to the juror’s motive, intent, or belief, or describing] their effect upon” the jury inhere in the verdict and cannot be considered. Gardner v. Malone, 60 Wn.2d 836, 841, 376 P.2d 651 (1962). This includes facts touching on the mental processes by which individual jurors arrived at the verdict, the effect the evidence may have *132had on the jurors, and the weight particular jurors may have given to particular evidence. Cox v. Charles Wright Acad., Inc., 70 Wn.2d 173, 179-80, 422 P.2d 515 (1967). A second test asks whether facts alleged in juror declarations can be rebutted by other testimony without probing any juror’s mental processes. Gardner, 60 Wn.2d at 841.
¶8 Circumstances in which it is “ ‘universally agreed’ ” that matters inhere in the verdict include when “ ‘one or more jurors misunderstood the judge’s instruction-, or were influenced by an illegal paper or by an improper remark of a fellow juror;... or had miscalculated accounts by errors of fact or of law.’ ” Id. at 841-42 (footnotes omitted) (quoting 8 John Henry Wigmore, Evidence in Trials at Common Law 681 (McNaughton rev. ed. 1961)). The policy behind refusing to consider matters that inhere in the verdict is to protect the sanctity of the jury room by “ ‘prevent [ing] the jury from divulging what considerations entered into its deliberations or controlled its action [s].’ ” Id. at 843 (quoting Md. Cas. Co. v. Seattle Elec. Co., 75 Wash. 430, 436, 134 P. 1097 (1913)). At the same time, the rule “ ‘does not close what is often the only avenue to a showing of actual facts constituting misconduct.’ ” Id. (quoting Md. Cas., 75 Wash. at 436).
¶9 Only if a court concludes that juror declarations allege actual facts constituting misconduct, rather than matters inhering in the verdict, does it proceed to “decide the effect the proved misconduct could have had upon the jury.” Id. at 841. A trial court’s decision in this regard will not be reversed on appeal unless the court abused its discretion. State v. Balisok, 123 Wn.2d 114, 117, 866 P.2d 631 (1994).
¶10 As noted, Long submitted declarations from 4 of the 12 empaneled jurors. He argues that the “unrebutted juror declarations prove that two jurors instructed the jury about outside Maritime and Coast Guard laws,” and that their statements introduced into the deliberations “definitive *133legal premises” comparable to erroneous jury instructions. Suppl. Br. of Pet’r Long at 8-9. We find the declarations to be more equivocal than Long suggests. We conclude they reveal matters that inhere in the verdict. Accordingly, there is no need to further consider the effect the alleged statements may have had on the verdict.
¶11 We begin by noting that the four juror declarations are not uniform in their description of the facts Long relies on to establish misconduct. For example, two of the declarations omit any reference to the second juror alleged to have introduced “definitive legal premises” into the deliberations. CP at 1783-89. With respect to juror 12, who is mentioned in all the declarations, the characterization of his actual statements varies among the four accounts. All give the impression that juror 12 was persuasive, opining that he “presented his position well,” CP at 1781, that he was “very authoritative about the content of his presentation,” CP at 1784, and that he “persuasively commanded the floor,” CP at 1788. And, they all note that he mentioned he had spent many years in the navy and was familiar with maritime laws, navy rules, boats, and boat safety. CP at 1780-92. But, exactly what juror 12 said about any applicable laws is less clear. For one thing, a second juror, identified in two of the declarations as “Robert P.” or “Bob P.,” reportedly offered his view that coast guard law would not allow a person with a prosthesis to work on the deck of a ship or boat. CP at 1781, 1791. This same juror is described as having “applied his experience in construction” to offer opinions on “sending people home from job sites if they didn’t have their physical or [urinary analysis test] completed.” CP at 1791.
¶12 Reading the declarations as a whole, it is difficult to ascertain the “definitive legal premises” that were allegedly introduced into the deliberations. Was it that navy and coast guard rules (or maritime law generally) disallow people with prosthetic limbs from working on ship decks; or instead that juror 12, being familiar with maritime laws *134generally, was unaware of any law that would have allowed Long to hire Morgan as a deckhand;2 or that it showed bad judgment to hire someone with a prosthesis to work on a deck;3 or something else? Indeed, one declaration states that the “point [juror 12] emphasized the most” was that “[h]e knew from serving on ships that boats are very dangerous, and that someone like Anthony Morgan should not be on a boat by law.” CP at 1788. Although this statement relates a general sense of “law,” it also reflects juror 12’s (strongly held) view based on his personal experience.4
¶13 We conclude that the matters revealed in the declarations inhere in the verdict and cannot be considered. Although portions of the declarations identify (in varying *135accounts) statements made by fellow jurors touching on questions of fact or law, these statements were expressions of personal belief based on life experiences. During jury deliberations, jurors may “rely on their personal life experience to evaluate the evidence presented at trial.” Breckenridge v. Valley Gen. Hosp., 150 Wn.2d 197, 199 n.3, 75 P.3d 944 (2003). Juror 12’s relevant life experiences were known to both parties, as he disclosed during voir dire that he was a retired member of the navy and an avid boater. See 1 VRP (Apr. 22, 2013) at 172 (juror 12 stated, “I’m retired from the U.S. Navy.. . . [M]y favorite activities are boating on Puget Sound, motorcycling, backpacking, and being a grandfather.”). Neither party exercised a peremptory strike against him. Drawing from his personal experiences, it is unsurprising that juror 12 opined about the legality and safety of allowing someone with a prosthetic leg to work on a ship. We have been reluctant to find juror misconduct when a juror injects personal knowledge and experience known to the parties into deliberations. McCoy v. Kent Nursery, Inc., 163 Wn. App. 744, 763-64, 260 P.3d 967 (2011) (finding no misconduct when juror drew on disclosed background in real estate and piping in tort action involving a failed pipe drainage system); Richards v. Overlake Hosp. Med. Ctr., 59 Wn. App. 266, 274, 796 P.2d 737 (1990) (finding no misconduct when jurors applied specialized medical knowledge during deliberations because that information was disclosed during voir dire).5
¶14 This case is similar to others in which we have rejected attempts to set aside a jury verdict on the ground that a juror brought specialized experience to bear on jury deliberations. In Breckenridge, the plaintiff sued her phy*136sician for medical negligence after she suffered a brain aneurysm, alleging that he “should have ordered a CT (computerized tomography) scan” during her emergency room visit. 150 Wn.2d at 198-99. Following a defense verdict, the plaintiff alleged juror misconduct because one of the jurors “related his experiences with his wife’s migraines during jury deliberations, comparing her symptoms to [the plaintiff’s symptoms].” Id. at 199. The juror also opined that the defendant was not negligent in treating the plaintiff because his wife received similar treatment. Id. at 206 (“Because [the juror] felt that his wife’s symptoms were similar to [the plaintiff’s] and his wife had not been given a CT scan, [the juror] believed that [the physician] was not negligent in his diagnosis and treatment of [the plaintiff].”). We concluded that the juror’s statements inhered in the verdict because the juror used his experience with his wife’s migraine headaches to evaluate the evidence presented at trial. Id.
¶15 In State v. McKenzie, this court reversed an order granting a new trial premised in part on juror misconduct. 56 Wn.2d 897, 355 P.2d 834 (1960). Concerning an eminent domain claim, we held that the trial judge improperly considered a juror declaration stating that “during the course of deliberations, one of the other jurors had argued (despite the trial court’s instruction to the contrary) that, as the juror understood the law, respondent had no right of access to primary state highway No. 18, for which compensation should be paid by the [S]tate.”M. at 900. Finding the matter attested to inhered in the verdict, though clearly a statement of the law, we “rather summarily dispose [d]” of the claim of misconduct. Id.; see also Johnston v. Sound Transfer Co., 53 Wn.2d 630, 631-32, 335 P.2d 598 (1959) (in action for injuries sustained while horseback riding, the fact that two jurors relayed their experiences about horseback riding inhered in the verdict); Marvin v. Yates, 26 Wash. 50, 60, 66 P. 131 (1901) (affidavit that jury used improper method to calculate damages inhered in the verdict).
*137 ¶16 Like the juror statements at issue in these prior cases, the juror statements here inhered in the verdict because they reflected personal beliefs based on life experiences. It is true that juror 12 and Robert R sometimes declared their views as a matter of fact or law; their fellow jurors—or at least the four who signed declarations— understood them to believe that a person with a prosthetic leg could not lawfully work as a deckhand. But, attaching the word “law” to their remarks, without more, does not change the fact that the jurors naturally used their life experiences to evaluate Long’s wrongful termination claim. We cannot know their intent and are not allowed to probe any juror’s thought processes. See Ayers, 117 Wn.2d at 768 (“[J]uror affidavits may not be used for the purpose of contesting the thought processes involved in reaching a verdict.”).
¶17 The circumstances here stand in contrast to those in which we have granted a new trial on the ground that empaneled jurors improperly introduced extrinsic evidence into jury deliberations. In such cases, the juror statements were plainly not matters of opinion based on personal experience, but expressions of law or fact based on outside sources. See, e.g., Bouton-Perkins Lumber Co. v. Huston, 81 Wash. 678, 680, 143 P. 146 (1914) (finding juror misconduct when, during deliberations, one juror “produced a pamphlet which purported to contain the forest protection laws of this state, and . . . portions of the pamphlet were read and commented upon”); Adkins v. Alum. Co. of Am., 110 Wn.2d 128, 131, 750 P.2d 1257, 756 P.2d 142 (1988) (granting new trial due to misconduct of bailiff and jury, where bailiff provided jury with Black’s Law Dictionary (1933) to look up definitions of “negligence” and “proximate cause”). Such misconduct warrants a new trial, just as surely as when an empaneled juror introduces into deliberations extrinsic facts about one of the parties. See, e.g., State v. Parker, 25 Wash. 405, 410, 65 P. 776 (1901) (granting new trial due to one juror’s statements during de*138liberations that he knew the defendant to be a member of a gang and to have been implicated in a murder; the juror had falsely denied any knowledge during voir dire). Here, we have only the somewhat conflicting declarations of four jurors, which characterize what one or two of their fellow jurors said based on their disclosed experiences. To consider such declarations would open the door to the impeachment of verdicts any time jurors make categorical assertions about what they believe the law to be based on their personal experience. This would undermine our “long held and cherished ambition [of] rendering . . . final and definitive judgments.” Cox, 70 Wn.2d at 180; see also Alger v. City of Mukilteo, 107 Wn.2d 541, 551, 730 P.2d 1333 (1987) (stating that courts have a strong interest in upholding jury verdicts).
CONCLUSION
¶18 Because the matters relayed in the juror declarations inhere in the verdict and cannot be considered, Long’s claim of juror misconduct fails. We affirm the lower courts’ denial of his motion for a new trial.
Madsen, C.J., and Owens, Gordon McCloud, and Yu, JJ., concur.All four declarations address statements made during deliberations by juror 12 (and two mention a second juror) regarding whether a person with a prosthesis could lawfully and safely work on a boat deck. Additionally, three of the declarations address statements made by jurors about what Long could earn as a firefighter or emergency medical technician. CP at 1781, 1785, 1791. Two of the declarations also address the jury’s reaction to a photograph defense counsel displayed of Bo Brusco and his wife on their honeymoon. CP at 1782, 1791. Although Long’s argument now focuses solely on juror statements concerning the first issue, the motion for new trial raised a separate allegation of juror misconduct concerning damages, as well as issues of misconduct by counsel. Long offered the juror declarations in support of all of these claims.
One juror said juror 12 talked about “Navy laws, and that none of the Coast Guard/Ocean/Maritime laws would allow anyone with prosthesis to work on the deck of either a ship or boat,’’ adding that “Robert P.” agreed as to coast guard law. CP at 1781. A second juror said juror 12 “talked at length about maritime laws, navy rules and repeated multiple times that no laws existed that would allow a deckhand with a prosthetic leg to be on a boat.’’ CP at 1784. A third declared that juror 12 “started by telling us that he had spent many years on ships and in the U.S. Navy and knew about the law, and about boats, and about safety. He said that he did not know of any law on the books including the Coast Guard laws that would every [sic] let someone [with a prosthesis] work as a deckhand on a boat.’’ CP at 1788. The fourth juror stated, “Dave [juror 12] mentioned that he spent many years in the Navy and is quite familiar with the laws of the organization and stated that there would be no way that the Navy (or other maritime organizations such as the Coast Guard) would have let a man with a prosthetic leg work on the deck of a ship. . . . Bob P. agreed.’’ CP at 1791.
One juror described juror 12 as having stated that “[Long’s] hiring Morgan showed very bad judgment.’’ CP at 1789.
Apart from their varying accounts of the facts, it is also notable that the four declarations reveal more about each juror’s impression of their fellow juror’s statements than the content of the statements. One juror observed that juror 12 “presented his position well, and relied on notes that appeared organized and prepared in advance.’’ CP at 1781. She stated, “I felt the expectation from [juror 12] to not interrupt.’’/d.Anotherjurornoted that juror 12 was “very authoritative’’ about the content of his presentation, even describing his manner as “very aggressive.’’ CP at 1784. A third juror felt that juror 12 “very persuasively commanded the floor,’’ and was “very convincing,’’ stating, “It really seemed to turn things around and get things heated up when he was done.’’ CP at 1788. With respect to “Bob R,” whose statements on this and other issues are identified, one juror declaration stated, “He became quite intense and vociferous several times which seemed to dominate the attitude in the room.’’ CP at 1791. These statements all describe the declarants’ perceptions of the other jurors’ remarks, which unquestionably inhere in the verdict.
Had any jurors failed to disclose their relevant background, this may have been a basis for finding misconduct. See Robinson v. Safeway Stores, Inc., 113 Wn.2d 154, 158-59, 776 P.2d 676 (1989) (misconduct when venire member failed to disclose bias against Californians in personal injury action by a California resident); Gordon v. Deer Park Sch. Dist. No. 414, 71 Wn.2d 119, 121, 426 P.2d 824 (1967) (misconduct when venire member failed to disclose prejudice in favor of schoolteachers in a personal injury action against a schoolteacher).