Under that rule, a cause of action accrues when the plaintiff knows he or she has been injured and has a "reason to connect [the injury] to a particular [cause, source, act, event, instrumentality, or condition] in such a way that a reasonable person would be on notice to investigate whether the injury might result from fault." Walk v. Ring , 202 Ariz. 310, 316, ¶ 22, 44 P.3d 990, 996 (2002) (emphasis added); see Doe v. Roe , 191 Ariz. 313, 322, ¶ 29, 955 P.2d 951, 960 (1998) ("A cause of action [accrues when] the plaintiff knows or with reasonable diligence should know the facts underlying the cause.") (emphasis added). ¶24 The State argues Humphrey's claim accrued as a matter of law by November 7, 2008, at the latest.

The date such a claim accrues is subject to the "discovery rule." See Walk v. Ring , 202 Ariz. 310, 314–17, ¶¶ 14–26, 44 P.3d 990, 994–96 (2002). Under that rule, a claim accrues when the plaintiff has reason to connect her injury with a "causative agent" such that "a reasonable person would be on notice to investigate whether the injury might result from fault."

Kiley v. Jennings, Strouss & Salmon, 187 Ariz. 136, 139, 927 P.2d 796, 799 (App. 1996). The two-year limitation begins upon discovery — that is, when a plaintiff knew or should have known of the negligence, its cause, and the resulting harm. Keonjian, 216 Ariz. at 565, ¶ 9, 169 P.3d at 929; see Walk v. Ring, 202 Ariz. 310, 316, ¶ 22, 44 P.3d 990, 996 (2002). In Walk, our supreme court stated that "it is not enough that a plaintiff comprehends a 'what'; there must also be reason to connect the 'what' to a particular 'who' in such a way that a reasonable person would be on notice to investigate whether the injury might result from fault."

The pertinent question thus is when did the Thompsons know or when should they reasonably have known the "cause, source, act, event, instrumentality or condition which caused or contributed to" Taylor's accident. § 12-821.01(B). ¶ 11 The Thompsons acknowledge that in Walk v. Ring, 202 Ariz. 310, ¶ 22, 44 P.3d 990, 996 (2002), our supreme court stated that for a cause of action to accrue, "it is not enough that a plaintiff comprehends a what'; there must also be reason to connect the `what' to a particular who' in such a way that a reasonable person would be on notice to investigate whether the injury might result from fault." They argue, however, that when "the facts are insufficient, and an investigation is needed to determine how the what' is related to the who', it seems that the investigation ought to be allowed to be completed before any time begins to run."

The relevant inquiry is when did a plaintiffs "`knowledge, understanding, and acceptance in the aggregate provide[] sufficient facts to constitute a cause of action.'" Walk v. Ring, 202 Ariz. 310, ¶ 23, 44 P.3d 990, 996 (2002), quoting Doe v. Roe, 191 Ariz. 313, ¶ 36, 955 P.2d 951, 962 (1998). ¶ 10 Here, we must determine whether the trial court correctly concluded that Johnson's filing the Board complaint on Little's behalf marked the accrual of her claim for purposes of § 12-821.0KB).

Citations to the docket are to page number added to the top of each page by the Court's CM/ECF system, not to original page numbers on the document. Defendants contend, pursuant to Walk v. Ring, 44 P.3d 990 (Ariz. 2002), that the evidence shows that Plaintiff's fiduciary duty claim accrued in 2009 or 2010, well outside of the two-year statute of limitations period. Plaintiff's knowledge of billing issues and Zowine's hostile conduct, Defendants assert, triggered a duty to investigate in 2010 and early 2011.

A plaintiff, however, "need not know all the facts underlying a cause of action to trigger accrual." Walk v. Ring, 202 Ariz. 310, 316 ¶ 22, 44 P.3d 990, 996 (2002) (quoting Doe, 191 Ariz. at 323 ¶ 32, 955 P.2d at 961). The ability "to identify that a wrong occurred and caused injury" is sufficient.

" Thompson v. Pima County, 226 Ariz. 42, 46, ¶ 12 (App. 2010). Under that rule, a cause of action accrues when the plaintiff knows he or she has been injured and has a "reason to connect [the injury] to a particular [cause, source, act, event, instrumentality, or condition] in such a way that a reasonable person would be on notice to investigate whether the injury might result from fault." Walk v. Ring, 202 Ariz. 310, 316, ¶ 22 (2002) (emphasis added); Doe v. Roe, 191 Ariz. 313, 322, ¶ 29 (1998) ("A cause of action [accrues when] the plaintiff knows or with reasonable diligence should know the facts underlying the cause.") (emphasis added). ¶22 The State argues Humphrey's claim accrued as a matter of law by November 7, 2008, at the latest; but Humphrey counters that accrual is a factual question that is "usually and necessarily" for the jury to determine and cannot be decided as a matter of law.

" Id. at 967. Courts have recognized that statutes of limitations are intended to protect defendants from stale claims where plaintiffs have slept on their rights, but "[a] blamelessly uninformed plaintiff cannot be said to have slept on his rights." Walk v. Ring, 44 P.3d 990, 995-96 (Ariz. 2002). The key "inquiry in applying the discovery rule is whether the plaintiff's injury or the conduct causing the injury is difficult for plaintiff to detect."

Put another way, "the core question" of when a claim accrued is not when the plaintiff was conclusively aware she had a cause of action against a particular party, but instead when "a reasonable person would have been on notice to investigate." Walk v. Ring , 202 Ariz. 310, ¶¶ 23–24, 44 P.3d 990, 996 (2002). ¶ 9 An abuse-of-process claim requires the plaintiff to show "(1) a willful act in the use of judicial process; (2) for an ulterior purpose not proper in the regular conduct of the proceedings."