Timothy Matthews v. ica/city of tucson/tristar

IN THE

SUPREME COURT OF THE STATE OF ARIZONA

TIMOTHY MATTHEWS,
Petitioner Employee,
v.

THE INDUSTRIAL COMMISSION OF ARIZONA,
Respondent,

CITY OF TUCSON,
Respondent Employer,

TRISTAR RISK MANAGEMENT,
Respondent Insurer.

No. CV-21-0192-PR
Filed November 23, 2022

Special Action - Industrial Commission
ICA Claim No. 20182-540202
Insurer No. 18736339
The Honorable Gary M. Israel, Administrative Law Judge
AFFIRMED

Opinion of the Court of Appeals, Division Two
251 Ariz. 561 (App. 2021)
AFFIRMED IN PART and VACATED IN PART

COUNSEL:

Laura Clymer (argued), Brian Clymer, Brian Clymer Attorney at Law,
Tucson, Attorneys for Timothy Matthews

M. Ted Moeller (argued), Karolyn F. Keller, Moeller Law Office, Tucson,
Attorneys for City of Tucson and Tristar Risk Management
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
Opinion of the Court

Robert J. Forman, Dix & Forman, PC, Tucson, Attorneys for Amicus Curiae
Arizona Association of Lawyers of Injured Workers

Kristin M. Mackin, William J. Sims III, Sims Mackin, Ltd. Phoenix,
Attorneys for Amici Arizona Municipal Risk Retention Pool and Arizona
Counties Insurance Pool

_______________

JUSTICE BOLICK authored the Opinion of the Court, in which CHIEF
JUSTICE BRUTINEL and JUSTICES LOPEZ, BEENE, MONTGOMERY,
and KING joined. VICE CHIEF JUSTICE TIMMER concurred in part and
dissented in part.
_______________

JUSTICE BOLICK, Opinion of the Court:

¶1 In this case, we hold that A.R.S. § 23-1043.01(B), which limits
workers’ compensation claims for mental illnesses to those that arise from
an “unexpected, unusual or extraordinary stress” situation, does not violate
article 18, section 8 of the Arizona Constitution or the equal protection
guarantee of article 2, section 13.

BACKGROUND

¶2 Timothy Matthews began training with the Tucson Police
Department (“TPD”) in August 2000 after passing the necessary pre-
employment physical and psychological examinations. Matthews
participated in TPD’s training program for four months.

¶3 After a four-month training program, Matthews worked as a
TPD patrol officer. In 2009 while off duty, Matthews passed by an accident
involving a car that hit a police officer on a bicycle. Matthews responded
to the scene. He later learned the officer had died. Afterward, Matthews
told his supervisor that the incident was negatively affecting him. He was
subsequently sent to a psychiatrist, but the incident was never reported as
an industrial accident for workers’ compensation purposes.

¶4 In 2011, Matthews was promoted to detective. He worked in
the violent crimes section for six years and then in the street crimes unit. In
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Opinion of the Court

March 2018, Matthews transferred to the domestic violence unit. During
these years, Matthews continued to receive professional mental health care.

¶5 In June 2018, Matthews responded to an active domestic
violence scene where an armed suspect was barricaded with his ex-wife and
stepson in a residential garage. While negotiators spoke with the armed
suspect, Matthews watched a live stream of the residence from a block
away. Eventually, the armed suspect released his ex-wife and stepson but
remained inside the garage.

¶6 Matthews obtained a search warrant for the SWAT team to
remove the suspect. Matthews also interviewed the ex-wife and stepson.
At some point, gunshots were heard from inside the garage. The sound
prompted officers stationed around the home to partially breach the garage
door. The suspect, visibly bleeding from a self-inflicted chest wound, then
attempted to crawl out of the garage with his hand raised. The responding
officers pulled him out of the garage and administered first aid, but the
suspect died at the scene. Matthews watched this unfold on the live stream.
He was later assigned to inspect the suspect’s body and photograph the
crime scene.

¶7 After this incident, Matthews began having nightmares,
flashbacks, and difficulties concentrating on the job. Matthews reported
these issues to his captain. Additionally, Matthews sought care from his
treating psychiatrist and the City of Tucson’s doctor. Both physicians
recommended Matthews be relieved from his work duties.

¶8 Matthews filed an industrial injury claim arising from the
June 2018 incident, claiming that it exacerbated his preexisting post-
traumatic stress disorder (“PTSD”). Tristar Risk Management, the City of
Tucson’s insurer, denied Matthews’ claim. Matthews protested the denial,
and a three-day hearing was held before an administrative law judge
(“ALJ”).

¶9 Matthews testified that the June 2018 incident was the most
recent of several incidents on the job that contributed to his PTSD.
However, he claimed the June 2018 incident was the “straw that broke the
camel’s back.” Matthews also presented Sergeant Daniel Spencer, his TPD
training supervisor, as an expert witness. Spencer testified that a domestic
violence barricade situation resulting in suicide happens about two to four

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Opinion of the Court

times a year. Additionally, Spencer testified that there were more than 100
officers in the area during the incident and that Matthews’ only unique
involvement was inspecting the suspect’s deceased body. Otherwise,
Spencer characterized the incident as a “standard issue.”

¶10 The City of Tucson and Tristar (the “City”) presented a
former Phoenix police officer and Dallas police chief, Benny Click. During
Click’s testimony, he expressed that the June 2018 incident was not unusual
for a law enforcement officer and that stress is an expected part of the job.
Click further testified that even incidents like a fellow officer being shot or
mass shootings are anticipated incidents.

¶11 In October 2019, the ALJ issued a decision finding Matthews’
claims for mental injuries non-compensable because the June 2018 incident
was not an “unexpected, unusual or extraordinary stress” situation as
required under § 23-1043.01(B). The ALJ did not consider Matthews’
testimony on the prior alleged PTSD-inducing incidents because he never
filed a gradual injury claim. Matthews requested agency review, arguing
that § 23-1043.01(B) violates article 18, section 8 of the Arizona Constitution
because it allows defendants to use an assumption of risk defense against
applicants. The ALJ affirmed the initial decision.

¶12 Matthews next filed a statutory special action petition with
the court of appeals. At oral argument, Matthews argued that
§ 23-1043.01(B) was unconstitutional under article 18, section 8 because the
original Workers’ Compensation Act (“WCA”) encompassed mental
injuries, and thus the legislature was restricted from treating them
differently than physical injuries. 1

¶13 In a divided opinion, the court of appeals affirmed the denial
of benefits. Matthews v. Indus. Comm’n, 251 Ariz. 561, 563 ¶ 1 (App. 2021).
The majority held that § 23-1043.01(B) did not unconstitutionally restrict
compensation but instead expanded it because the framers of the Arizona
Constitution never contemplated mental injuries when they used the term
“injury.” Id. at 569–70 ¶ 19.

¶14 The dissent argued that “injury” should be read more broadly
and in the context of article 18, section 8’s language, of any accident arising

1In 1912 the WCA was originally titled the Workman’s Compulsory
Compensation Act. 1912 Ariz. Sess. Laws ch. 14 (Spec. Sess.).
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out of and in the course of employment. Id. at 344 ¶ 30 (Eckerstrom, J.,
dissenting). The dissent construed “accident” in the workers’
compensation context to encompass both unexpected workplace events and
injuries arising from the workplace. Id. Therefore, the dissent concluded
that by subjecting compensation for such injuries and accidents to
additional requirements, § 23-1043.01(B) unconstitutionally barred
Matthews from the benefits to which he is entitled under the WCA. Id.
at 345 ¶ 33.

¶15 We granted review to consider whether § 23-1043.01(B) is
unconstitutional as applied to claimants who work in high-stress
occupations such as law enforcement. This issue is a matter of statewide
concern. We have jurisdiction under article 6, section 5(3) of the Arizona
Constitution.

DISCUSSION

¶16 A challenge to a statute’s constitutionality presents a question
of law, which we review de novo. State v. Hansen, 215 Ariz. 287, 289 ¶ 6
(2007).

I. ARTICLE 18, SECTION 8 OF THE ARIZONA CONSTITUTION

A.

¶17 Article 18, section 8 provides in relevant part:

The legislature shall enact a workmen’s compensation law
applicable to workmen engaged in manual or mechanical
labor in all public employment whether of the state, or any
political subdivision or municipality thereof as may be
defined by law and in such private employments as the
legislature may prescribe by which compensation shall be
required to be paid to any such workman, in case of his injury
and to his dependents, as defined by law, in case of his death,
by his employer, if in the course of such employment personal
injury to or death of any such workman from any accident
arising out of and in the course of, such employment, is
caused in whole, or in part, or is contributed to, by a necessary
risk or danger of such employment, or a necessary risk or
danger inherent in the nature thereof, or by failure of such
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Opinion of the Court

employer, or any of his or its agents or employee or
employees to exercise due care, or to comply with any law
affecting such employment . . . .

¶18 The controlling language from the constitutional provision is
coverage for an “injury . . . from any accident” arising from “a necessary
risk or danger” of the employment. Ariz. Const. art. 18, § 8. Matthews
argues that by requiring workers’ compensation claimants to prove their
mental injuries were caused by “unexpected, unusual or extraordinary
stress,” § 23-1043.01(B) unconstitutionally restricts legal causation by
creating an assumption of the risk defense.

¶19 In deciding this question, we must first determine whether
article 18, section 8 of the Arizona Constitution encompasses mental stress
injuries; that is, mental illnesses brought on not by physical trauma but by
mental trauma such as stress or shock. See Tucson Unified Sch. Dist. v. Indus.
Comm’n, 198 Ariz. 133, 134 ¶ 7 (App. 2000). If it does not, as the court of
appeals majority concluded, then the statute does not violate article 18,
section 8 because the legislature is free to enlarge the scope of workers’
compensation. Goodyear Aircraft Corp. v. Indus. Comm’n, 62 Ariz. 398, 408
(1945) (“Sec. 8 of article 18 . . . is not a grant of power to the legislature, but
a command directing it to exercise a power which it already possessed. The
constitutional mandate does not restrict the legislature in its inherent
powers to go beyond the terms of the Constitution in making injuries from
accidents, which are not mentioned therein, compensable.”). If the
constitutional provision does encompass mental stress injuries, as the
dissent concluded, we must then determine whether the statute adds
impermissible obstacles to workers’ compensation. See Grammatico v. Indus.
Comm’n, 211 Ariz. 67, 75 ¶ 35 (2005) (striking down a different part of the
statute because it expanded the constitution’s proof requirements).
Although this Court has frequently construed both the constitutional
provision and § 23-1043.01, we have never determined whether article 18,
section 8 provides workers’ compensation for mental stress injuries. See,
e.g., France v. Indus. Comm’n, 250 Ariz. 487, 488 ¶ 2 n.1 (2021).

¶20 Our relevant case law is circuitous and contradictory and
does not resolve this question. In Pierce v. Phelps Dodge Corp., 42 Ariz. 436
(1933), this Court rejected a claim for death from acute myocarditis that was
accelerated by work conditions, holding that the term “accident” in the
constitutional provision meant an unexpected event that caused an injury.
Id. at 446–47. This view was rejected in Paulley v. Indus. Comm’n, 91 Ariz.
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266 (1962), which held that “injury by accident” occurs “when either the
external cause or the resulting injury itself is unexpected or accidental.” Id.
at 272. Neither Paulley nor the cases following Pierce on which it relied
involved mental stress injuries.

¶21 In Brock v. Indus. Comm’n, 15 Ariz. App. 95 (1971), the
workers’ compensation claimant was a truck driver who previously
suffered from depression, which was aggravated by an incident in which
he ran over and killed a woman, did not realize he had done so until
informed by the police, and was subsequently suspended and investigated.
Id. at 95–96. The court of appeals held that “the presence of a physical force
or exertion [is] not a necessary element to the determination that the
claimant had been ‘injured by accident,’” and that “it is now commonly
viewed to include any unexpected injury-causing event, so long as it is
work-connected.” Id. at 96.

¶22 The next year, the court of appeals held that where anxiety
neurosis was caused not by an “unexpected injury-causing event but rather
a buildup of emotional stress for a period of years,” it was not compensable
because it was “part of the usual, ordinary and expected incidents of his
employment.” Shope v. Indus. Comm’n, 17 Ariz. App. 23, 25 (1972).

¶23 In Fireman’s Fund Ins. Co. v. Indus. Comm’n, 119 Ariz. 51 (1978),
this Court held that a claim for a mental breakdown that resulted from
steadily increased work responsibility was compensable. Id. at 54–55. The
Court reasoned that “[p]hysical impact or exertion is not a necessary
element in determining whether an injury has, in fact, occurred,” id. at 54,
and that “by definition, an injury is caused by accident when the resulting
injury is unexpected.” Id. at 53.

¶24 Justice Gordon dissented, emphasizing that “the Act was not
intended to be a general health and accident insurance substitute.” Id. at 55
(Gordon, J., dissenting) (citing Cavness v. Indus. Comm’n, 74 Ariz. 27 (1952)).
He declared that an “award for a mental condition brought about by the
gradual build-up of emotional stress over a period of time, without an
injury-causing event, paves the way for tomorrow’s abuses of the
workmen’s compensation system.” Id. He called on the Court to adhere to
“the concrete standard established by Shope,” and urged that “this is a step
which should be taken by the Legislature, rather than by further judicial
modification” of injury-by-accident. Id.

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¶25 A few months later, the Court again took up compensation
for a disability brought about by emotional stress. Sloss v. Indus. Comm’n,
121 Ariz. 10 (1978). Noting Fireman’s Fund held that physical force was not
necessary to establish injury, the Court nonetheless held that to “qualify as
an injury by accident, the condition must have been produced by the
unexpected, the unusual, or the extraordinary stress.” Id. at 11.

¶26 The year after Sloss, the legislature enacted § 23-1043.01. At
issue here is subsection B, providing as follows:

A mental injury, illness or condition shall not be considered a
personal injury by accident arising out of and in the course of
employment and is not compensable pursuant to this chapter
unless some unexpected, unusual or extraordinary stress
related to the employment or some physical injury related to
the employment was a substantial contributing cause of the
mental injury, illness or condition.

§ 23-1043.01(B). This language essentially codified the holding in Sloss.

¶27 In Grammatico, ¶ 19, the Court concluded that A.R.S. § 23-
1021(D), which required proof that the presence of alcohol or illegal drugs
was not a contributing cause of an accident to qualify for workers’
compensation, violated article 18, section 8. Grammatico, 211 Ariz.
at 75 ¶ 35. The Court reasoned that although the constitutional provision
does not limit the legislature’s power to define medical causation, that is,
whether the accident caused the injury, the legislature may not alter legal
causation as defined by article 18, section 8. Id. at 72 ¶¶ 20–21. Because the
constitutional provision provides compensation where a necessary risk of
employment contributed to the industrial accident (legal causation),
requiring claimants to prove drugs and alcohol were not a factor rendered
the provision unconstitutional. Id. at ¶ 23. Matthews invokes Grammatico
to argue that subsection B likewise alters the constitutional definition of
legal causation because it adds the requirement that the injury-causing
accident must be “unexpected, unusual or extraordinary.” 2

2“Legal causation concerns whether the injury arose out of and in the course
of the employment on the other hand, medical causation ordinarily requires
expert medical testimony to establish that the industrial accident caused the
injury.” DeSchaaf v. Indus. Comm'n, 141 Ariz. 318, 320 (App. 1984). (internal
citation omitted).
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¶28 Most recently, in France, we held that a deputy who
developed PTSD after he shot and killed a man who threatened him with a
shotgun during a welfare check was entitled to compensation under
§ 23-1043.01(B) because the precipitating event was “unexpected, unusual
or extraordinary.” France, 250 Ariz. at 488 ¶ 1. Because we concluded that
the illness was compensable under the statute, we did not address the
statute’s constitutionality. Id. at n.1. That is the question now before us.

B.

¶29 Given the constitutional authority vested in the legislative
branch, we do not lightly overturn statutes. See Ariz. Const. art. 4, pt. 1, § 1;
see also Ariz. Const. art. 18, § 8 (“The legislature shall enact a workmen’s
compensation law applicable to workmen engaged in manual or
mechanical labor in all public employment . . . .”); State v. Hulsey, 243 Ariz.
367, 386 ¶ 73 (2018); San Carlos Apache Tribe v. Superior Court, 193 Ariz. 195,
204 ¶ 11 (1999). When construing a constitutional provision, we seek to
give terms the original public meaning understood by those who used and
approved them. See, e.g., State ex rel. Brnovich v. City of Phoenix, 249 Ariz.
239, 244 ¶ 21 (2020) (“[W]e give the words their ordinary meaning, unless
the context suggests a different one.”); Golder v. Dep’t of Revenue, 123 Ariz.
260, 265 (1979) (“The intent of the Legislature can only be determined by
the language used, aided by the canons and rules of construction founded
upon reason and experience.” (quoting Barlow v. Jones, 37 Ariz. 396, 399
(1930))); District of Columbia v. Heller, 554 U.S. 570, 576–77 (2008).

¶30 The Court has not examined the original public meaning of
the key terms in article 18, section 8 for nearly a century. See Pierce, 42 Ariz.
at 446. Thus, to determine whether the legislature permissibly expanded or
improperly contracted workers’ compensation eligibility in § 23-1043.01(B),
we must ascertain the original public meaning of the key terms used in
article 18, section 8.

¶31 Matthews focuses on the constitutional provision’s words,
“necessary risk or danger of such employment.” By adding the statutory
modifier “unexpected, unusual or extraordinary,” Matthews argues, the
legislature unconstitutionally constrained the types of risks that could
trigger workers’ compensation eligibility. The court of appeals’ dissent
likewise urges that “the criteria for sorting compensable mental injury
claims from non-compensable ones cannot constitutionally exclude claims

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Opinion of the Court

that arise from predictable hazards of the workplace.” Matthews, 251 Ariz.
at 572–73 ¶ 32 (Eckerstrom, J., dissenting).

¶32 But that begs the question: what claims are encompassed by
article 18, section 8? All agree that an injury by accident is the predicate for
coverage. If the definition of those terms when our constitution was
adopted in 1912 did not encompass mental stress injuries, then such
coverage exists only to the extent it has subsequently been made available
by the legislature. See Atkinson, Kier Bros., Spicer Co. v. Indus. Comm’n,
35 Ariz. 48, 52–53 (1929) (upholding the legislature’s action to provide
coverage beyond “workmen engaged in manual or mechanical labor,” as
originally provided in article 18, section 8).

¶33 Our examination of original public meaning starts with
dictionary definitions from the time the provision was adopted. See, e.g.,
Burns v. Ariz. Pub. Serv. Co., 517 P.3d 624, 630 ¶ 25 (Ariz. 2022). Our work
also can be aided by corpus linguistics, which employs a massive database
that enables date-specific searches for the possible, common, and most
common uses of words or phrases as they were used in newspapers, books,
magazines, and other popular publications. Thomas R. Lee & Stephen C.
Mouritsen, Judging Ordinary Meaning, 127 Yale L.J. 788, 831–32 (2018).
Many courts have employed corpus linguistics in similar contexts to
determine the ordinary meaning of terms when they were put into statutory
or constitutional use. See, e.g., Fulkerson v. Unum Life Ins. Co. of Am., 36 F.4th
678, 682–83 (6th Cir. 2022) (using corpus linguistics to determine the
meaning of “reckless driving”); United States v. Rice, 36 F.4th 578, 583 n.6
(4th Cir. 2022) (using corpus linguistics to assess whether strangulation
requires intent); In re Estate of Heater, 498 P.3d 883, 890 ¶ 35 (Utah 2021)
(applying corpus linguistics to define “natural parent”); Bright v. Sorensen,
463 P.3d 626, 638–39 ¶¶ 56–57 (Utah 2020) (“foreign object”); Richards v.
Cox, 450 P.3d 1074, 1079–80 ¶¶ 19–25 (Utah 2019) (“employment in”); State
v. Lantis, 447 P.3d 875, 880–81 (Idaho 2019) (“disturbing the peace”); People
v. Harris, 885 N.W.2d 832, 839 (Mich. 2016) (“information”).

¶34 In some past cases the Court has embraced the general rule
that “because constitutions are for the purpose of laying down broad
general principles, and not the expression of minute details of law, their
terms are to be construed liberally, for the purpose of giving effect to the
general meaning and spirit of the instrument, rather than as limited by
technical rules of grammar.” State ex rel. La Prade v. Cox, 43 Ariz. 174, 177–
78 (1934). With due respect to our judicial forebears, we are neither
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authorized nor competent to discern the “spirit” of a constitutional
provision nor to effectuate what we divine in that regard. See Antonin
Scalia & Bryan A. Garner, Reading Law: The Interpretation of Legal Texts 344
(2012) (“[T]he ‘spirit’ of laws is the unhappy interpretive conception of a
supposedly better policy than can be found in the words of an authoritative
text. It is an unreliable nonstandard.”). Rather, we apply the constitution’s
plain meaning. See, e.g., Golder, 123 Ariz. at 265. Moreover, while terms
such as “due process of law” and “equal protection of the laws” are indeed
general, the constitutional language here exhibits far greater specificity,
commanding coverage only for (1) an injury (2) occurring by accident (3)
that is a necessary risk or danger of employment. Ariz. Const. art. 18, § 8.
Because of that triple qualifier, it has aptly been observed that workers’
compensation is not general insurance coverage but only covers the
instances specified in the constitution or by the legislature. Cavness, 74 Ariz.
at 30. Only the legislature or the people acting in their legislative capacity
may expand those terms, not the courts.

¶35 Turning to the actual language, the dissent effectively takes
the unsupported position that a possible meaning within the dictionary
definition is sufficient to infuse a constitutional or statutory provision with
that meaning. Infra ¶ 57. To the contrary, “we give the words their
ordinary meaning, unless the context suggests a different one.” State ex rel.
Brnovich, 249 Ariz. at 244 ¶ 21. Corpus linguistics is useful in assessing
whether a possible meaning was a common one when the words were
adopted in law, such that we can assume that the legislature or electorate
understood a term to encompass that particular meaning.

¶36 An authoritative dictionary published at the time our
constitution was adopted defines “injury” as “that which occasions harm
morally or physically; detriment; loss; damage.” Injury, New Websterian
Dictionary (1912). That definition reflects its common usage at the time. A
corpus linguistics review of the term reveals that “injury” connotes
physical, reputational, community (e.g., a person has “done the city a
greater injury than any man who ever lived in Westville”), or property
harm. Search of “Injury” from 1912, Corpus of Hist. Am. Eng.,
https://www.english-corpora.org/coha/ (last visited Nov. 14, 2022)
(populating 60 source references). These popular usages contained no
references to any type of illness or mental harm. Together, these sources
indicate that stress-related illness would not have been considered an
“injury” when the constitutional provision was adopted.

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¶37 Similarly, in 1912, “accident” was defined as “an event which
is unexpected, or the cause of which was unforeseen; a contingency,
casualty, or mishap; a property of a thing which is not essential to it.”
Accident, New Websterian Dictionary (1912). References in popular culture
depicted an accident as a solitary, unexpected event; a diversion from the
ordinary course of events. Search of “Accident” from 1912, Corpus of Hist.
Am. Eng., https://www.english-corpora.org/coha/ (last visited Nov. 14,
2022) (populating 89 source references). The term was frequently
juxtaposed against sickness or illness (that is, “accident or sickness,”
“accident or illness”). Id. Thus, in 1912, the plain meaning of an injury by
accident would be physical damage caused by a singular, unexpected
event.

¶38 Importantly, none of the common uses identified through
corpus linguistics encompass the meaning the dissent attaches to accident
by injury: a traumatic event or series of events, whether anticipated in the
scope of employment or not, that cause or exacerbate a serious mental stress
illness.

¶39 The dissent contends that in searching for the original public
meaning of injury by accident, we should not be looking at 1912, when
article 18, section 8 was adopted, but at 1925, when the voters ratified
significant changes. Infra ¶ 63. That year, as the dissent observes, the
legislature and the voters amended the provision to create an industrial
commission, establish a state compensation fund, include death benefits,
and expand coverage to workers in non-dangerous occupations. Infra ¶ 63.

¶40 What the amendments did not do is alter in any way the injury
by accident language. When a subsequent enactment imports unchanged
earlier language, it imports the original meaning as well. See Scalia &
Garner, supra, at 323 (“[W]hen a statute uses the very same terminology as
an earlier statute [,] especially in the very same field[,] . . . it is reasonable to
believe that the terminology bears a consistent meaning. One might even
say that the body of law of which a statute forms a part—especially if that
body has been codified—is part of the statute’s context.”).

¶41 Regardless, the temporal focus urged by the dissent appears
to make no difference. The dissent posits that between 1912 and 1925, the
experience of World War I surely must have broadened the understanding
of “accident” and “injury” to encompass trauma-induced mental stress

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injuries such as shell shock. Infra ¶ 65. But neither the dictionary
definitions nor common usage of those terms changed. See Accident,
Baldwin’s Century Edition of Bouvier’s Law Dictionary (1926) (“An event
which, under the circumstances, is unusual and unexpected by the person
to whom it happens”); Accident, Collegiate Law Dictionary (1925) (“An
event that takes place without one’s foresight or expectation; an event
which proceeds from an unknown cause, or is an unusual effect of a known
cause, and therefore not expected”); see Injury, Webster’s New Modern
English Dictionary (1922) (defining injury as “injuries that which occasions
harm morally or physically; detriment; loss; damage”). These definitions,
consistent with the 1912 version, contemplate “accident” as a singular,
unforeseeable event or effect; and “injury” as encompassing specific types
of harm that did not include trauma-induced stress injuries. Such injuries
were certainly known following World War I, but perhaps were more likely
thought of as illness, disease, or condition. See, e.g., Illness, Baldwin’s
Century Edition of Bouvier’s Law Dictionary (1926) (defining illness in the
insurance context as “a disease or ailment of such a character as to affect the
general soundness, and healthfulness of the system.”). But article 18,
section 8 uses the terms “injury” and “accident,” not “illness,” “disease,” or
“condition.”

¶42 Nor did the idea of trauma-induced mental stress injuries
enter the popular lexicon as injuries or accidents. A corpus linguistics
analysis reveals that references to “injury” in common usage pertained to
physical, property, community, or economic harm, just as they did in 1912.
Search of “Injury” from 1925, Corpus of Hist. Am. Eng.,
https://www.english-corpora.org/coha/ (last visited Nov. 14, 2022)
(populating 27 source references). Popular uses of “accident” pertained to
a single unexpected event, as contrasted from purposeful actions or disease.
Search of “Accident” from 1925, Corpus of Hist. Am. Eng.,
https://www.english-corpora.org/coha/ (last visited Nov. 14, 2022)
(populating 60 source references). Again, none of the identified popular
uses involved trauma-induced mental injuries. It is therefore exceedingly
difficult to conclude, as the dissent does, infra ¶66, that “1925 voters
undoubtedly understood these terms as including mental injuries.”

¶43 Only eight years later in Pierce, the seminal 1933 case
construing “injury by accident,” the Court meticulously examined the
meaning of the constitutional language. Using dictionary meaning, the
Court, much as we have above, defined “injury” as “damage,” and

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“accident” as “an undesigned, sudden and unexpected event.” 42 Ariz. at
442. The Court also focused on the preposition “by,” noting that in
isolation, an accident can be a cause or a result; but that when preceded by
the preposition, it can only be a cause. Id. Thus, the Court concluded that
eligibility for workers’ compensation requires an unexpected event that
caused an injury. Id. at 446.

¶44 We are persuaded that the original, plain meaning of injury
by accident requires more than the ordinary stresses presented by a specific
job, but rather an unexpected event resulting in tangible physical harm.
Therefore, §23-1043.01(B) supplements the constitutional requirement, as
described the year prior to its adoption in Sloss.

¶45 Matthews argues that the meaning of injury by accident, as
reflected in several post-Pierce cases, has evolved over time. He cites a
workers’ compensation treatise for the proposition that “modern medical
opinion” supports the view that “there really is no valid distinction
between physical and ‘nervous’ injury,” and that legal theory is “constantly
adapting itself to accommodate new advances and knowledge in medical
theory.” See 4 Lex K. Larson & Thomas A. Robinson, Larson’s Workers’
Compensation Law §56.04 (2020).

¶46 We do not hitch constitutional meaning to the evolving state
of scientific art or “modern medical opinion.” Such changes or advances
are relevant to medical causation, which the parties agree is established in
this case, but not to legal causation, which is defined here by the
constitution. It may be that our organic law and statutes should be revised
to reflect advances in medical understanding. The power to do so,
however, resides exclusively in the people and their elected representatives,
not the courts. Ariz. Const. art. 3; see also Cavness, 74 Ariz. at 30 (“Protection
to workmen and their dependents is limited to injuries by accident arising
out of and in the course of employment and we recognize that in no event
must the workmen’s compensation law be converted into a general health
and accident coverage.”). Article 18, section 8 is a mandate that the
legislature enact a workers’ compensation scheme, reposing in the
legislature the discretion to decide its parameters beyond its core
requirements. Section 23-1043.01(B) aligns with the constitutional directive
to compensate some injuries caused by work-related accidents and reflects
a permissible policy change expanding workers’ compensation.

14
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Opinion of the Court

¶47 In urging that we strike down § 23-1043.01(B), the dissent
essentially argues that sometime over the past 110 years, article 18, section 8
was transformed from a limited workers’ compensation mandate into one
requiring general insurance coverage for whatever injuries or events might
be shoehorned into the categories of injury and accident, construing those
terms in the broadest possible way. Instead, the constitutional provision
required the legislature to create a workers’ compensation system, which it
did in 1925 by expanding the classes of eligible beneficiaries while not
expanding the scope of coverage. Many years later, following this Court’s
decision in Sloss, the legislature expanded the scope of coverage, within
limits it deemed appropriate, by enacting § 23-1043.01(B). In other words,
with the adoption of § 23-1043.01(B), mental stress caused by mental
trauma was recognized as an “injury” in Arizona law. The legislature also
provided therapy and counseling employment benefits to individuals
employed in public safety, policing, and firefighting occupations. A.R.S.
§§ 38-672, -673. These benefits supplement those mandated in 1912 and
1925. Therefore, we have no occasion to invalidate § 23-1043.01(B).

¶48 Our decision does not leave workers unprotected against
mental injuries. Quite the contrary. See, e.g., France, 250 Ariz. at 488 ¶¶ 1– 2.
However, the ALJ properly relied on extensive evidence that the
traumatizing events Matthews experienced were a known and expected
danger of the job. Accordingly, we affirm the ALJ’s award determination.

¶49 We do not here revisit past cases to the extent they are
consistent with this opinion. We hold only that § 23-1043.01(B) does not
violate article 18, section 8’s limited mandate.

II. EQUAL PROTECTION

¶50 Our federal and state constitutional guarantees of equal
protection of the laws require the government to justify legal classifications
that subject individuals to adverse treatment. See, e.g., City of Cleburne v.
Cleburne Living Center, 473 U.S. 432, 439 (1985) (holding that equal
protection “is essentially a direction that all persons similarly situated
should be treated alike”). Matthews contends that § 23-1043.01(B) violates
this guarantee by requiring workers who have suffered mental stress
injuries to meet a higher standard of proof—i.e., that the injury was caused
by “unexpected, unusual or extraordinary stress”— to qualify for workers’
compensation. As noted above, supra ¶ 20, the constitutional definition of

15
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Opinion of the Court

injury by accident necessarily entails an unexpected event; thus, the
differential treatment Matthews alleges does not appear here.

¶51 Nor does the statute discriminate among workers who are
subject to its terms. Findley v. Indus. Comm’n, 135 Ariz. 273, 276 (App. 1983).
As the court of appeals noted in Findley “all members of a class, those with
stress-related mental injuries or illnesses, are treated equally by the
statute.” Id.

¶52 Even assuming that § 23-1043.01(B) does subject different
classes of workers to different standards, those standards are based on a
genuine difference among classes of workers. See Cleburne, 473 U.S.
at 441– 42 (recognizing that a “distinctive legislative response” is justified
where “individuals in the group affected by a law have distinguishing
characteristics relevant to interests the State has the authority to
implement”). The court of appeals held in Findley that “[g]iven the
difficulty in proving the causal connection between mental illness and the
work place, the legislature could constitutionally provide a more stringent
proof classification for these types of injuries.” 135 Ariz. at 276. We agree
that § 23-1043.01(B) does not subject workers with stress-related injuries to
unconstitutional discrimination.

CONCLUSION

¶53 Section 23-1043.01(B), which has governed compensation of
stress-related workplace injuries for more than four decades, does not
unconstitutionally limit recovery for such injuries. The challenged statute
provides workers’ compensation eligibility beyond that required by article
18, section 8, which is the legislature’s prerogative.

¶54 For the foregoing reasons, we affirm the decision of the court
of appeals while vacating paragraphs 9–19 of its opinion and affirm the
ALJ’s award determination.

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 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

TIMMER, VCJ., concurring in part and dissenting in part.

¶55 I agree with my colleagues that A.R.S. § 23-1043.01(B) does
not violate the equal protection guarantees of the state and federal
constitutions. But because I interpret article 18, section 8 of the Arizona
Constitution (“Section Eight”) differently from the majority, I conclude
§ 23-1043.01(B) violates Section Eight. I therefore respectfully dissent from
the majority’s contrary position.

I. Defining “Injury” and “Personal Injury”

¶56 In interpreting Section Eight, “our primary goal is to
effectuate the electorate’s intent in adopting it” and in doing so, “we give
the words their ordinary meaning, unless the context suggests a different
one.” See State ex rel. Brnovich v. City of Phoenix, 249 Ariz. 239, 244 ¶ 21
(2020). In my view, the majority misidentifies the ordinary meaning of
“injury” and “personal injury” in Section Eight by defining those words as
“physical damage.” See supra ¶¶ 36-37.

¶57 First, nothing in Section Eight limits “injury” or “personal
injury” to “physical damage.” Dictionaries at the time voters ratified the
constitution defined “injury” broadly. 3 The 1912 definition of “injury” cited
by the majority includes “detriment” and “damage,” both of which
sufficiently describe a mental injury as well as a physical one. See supra
¶ 36. More pointedly, the 1909 Webster’s New International Dictionary
defined “injure” in part as “[t]o do harm to; to hurt; damage; impair; to hurt
or wound, as the person; to impair the soundness of, as health.” Injure,
Webster’s New International Dictionary (1909). Similarly, “injury”
included “[d]amage or hurt done to or suffered by a person.” Injury,
Webster’s New International Dictionary (1909). And before 1912, people
had long recognized that mental impairments could be “injuries.” See, e.g.,
Injury, Am. Dictionary of the Eng. Language,
https://webstersdictionary1828.com/Dictionary/injury (last visited Nov.
15, 2022) (defining “injury” in part as “[t]hat which impairs the mental
faculties.”). Indeed, the 1912 Workman’s Compulsory Compensation Act,

3
Although voters ratified the constitution in December 1911, the majority
focuses on the meaning of “injury” and “personal injury” in 1912, when
Arizona became a state. For consistency, I likewise refer to 1912 as the
pertinent ratification time frame.
17
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

enacted as required by Section Eight, recognized that workplace injuries
could result in mental injuries. See Workman’s Compulsory Compensation
Act, 1912 Ariz. Sess. Laws ch. 14, § 13 (Spec. Sess.) (providing protective
procedures for injured workers rendered “mentally incompetent”).

¶58 The majority is nevertheless persuaded to confine “injury” to
physical trauma because a corpus linguistics review of the word in 1912 did
not link it with “any type of illness or mental harm.” See supra ¶ 36. The
majority does not provide sufficient information about the corpus
linguistics database to comfortably conclude it represents an adequate
number and variety of publications to accurately reflect popular usage of
“injury” in 1912. The fact that sixty written references to “injury” did not
link the word to a mental injury is underwhelming, particularly as one
would expect more references to such a common word. Id. And corpus
linguistics does not reflect oral usage of “injury” in 1912. For these reasons,
I place more weight on the dictionary definitions of the time as evidencing
the ordinary meaning of “injury” and “personal injury.”

¶59 Regardless, my own search of the corpus linguistics database
reveals writings reflecting public awareness that stressful events (an
accident) could injure a person’s mental health (an injury). See Search of
“Mental Shock” from 1885 to 1917, Corpus of Hist. Am. Eng.,
https://www.english-corpora.org/coha/ (last visited Nov. 16, 2022)
(populating thirteen source references, collectively). For example, in 1886
Oliver Wendell Holmes, Sr., father of the famous jurist, published “A
Mortal Antipathy: First Opening of the New Portfolio,” a novel
acknowledging that a “sudden mental shock” may cause insanity and other
mental injuries:
[T]he records of our asylums could furnish many cases where
insanity was caused by a sudden fright.

More than this, hardly a year passes that we do not read of
some person, a child commonly, killed outright by terror,—
scared to death, literally. Sad cases they often are, in which,
nothing but a surprise being intended, the shock has instantly
arrested the movements on which life depends. If a mere
instantaneous impression can produce effects like these, such
an impression might of course be followed by consequences
less fatal or formidable, but yet serious in their nature. If here
18
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

and there a person is killed, as if by lightning, by a sudden
startling sight or sound, there must be more numerous cases
in which a terrible shock is produced by similar apparently
insignificant causes,—a shock which falls short of
overthrowing the reason and does not destroy life, yet leaves
a lasting effect upon the subject of it.

Oliver Wendell Homes, A Mortal Antipathy, Project Gutenberg,
https://www.gutenberg.org/files/2698/2698-h/2698-h.htm (Feb. 18,
2018) (Chapter VII).

¶60 As another example, just a year after Arizona entered
statehood, novelist Frances Hodgson Burnett, author of children’s classics
like “The Secret Garden” and “Little Lord Fauntleroy,” published “T.
Tembarom,” which described a stranger who “slept a great deal and was
very quiet.” Frances Hodgson Burnett, T. Tembarom, Project Gutenberg
(Feb. 1, 2001), https://www.gutenberg.org/cache/epub/2514/pg2514-
images.html (Chapter VI). An examining doctor found no evidence of head
trauma and yet noted the stranger’s condition “was frequently the result of
concussion of the brain, sometimes of prolonged nervous strain or harrowing
mental shock.” Id. (emphasis added); see also Frances Hodgson Burnett, The
Shuttle, Project Gutenberg (Mar. 18, 2006),
https://www.gutenberg.org/cache/epub/506/pg506-images.html
(writing in 1907 that “[i]t could not be denied that Buttle received a mental
shock which verged in its suddenness on being almost a physical
one”(emphasis added)).

¶61 “Injury” and “personal injury” are general terms with wide-
ranging ordinary meanings, and we should apply those meanings within
the framework of Section Eight. See Antonin Scalia & Bryan A. Garner,
Reading Law: The Interpretation of Legal Texts 101 (2012) (“[I]n the end,
general words are general words, and they must be given general effect.”).
Dictionaries and writings from the turn of last century support concluding
that the ordinary meaning of “injury” and “personal injury” encompasses
mental injuries. Section Eight’s requirement that compensable injuries
result “from any accident” on the job does not confine the meaning of
“injury” to physical injury. Thus, in my view, a covered worker who incurs
a mental injury from an on-the-job accident caused at least partially by “a

19
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

necessary risk or danger” of the employment or the failure of the employer
to “exercise due care” or follow an employment law, is constitutionally
entitled to workers’ compensation. See Ariz. Const. art. 18, § 8.

¶62 Second, I disagree with the majority’s focus on the meaning
of “injury” and “personal injury” in 1912. The original version of Section
Eight had narrower application and did not apply to law enforcement
officers like Matthews. See Ariz. Const. art. 18, § 8 (1912) (requiring
coverage for “such employments as the Legislature may determine to be
especially dangerous”); 1912 Ariz. Sess. Laws ch. 14, § 3 (Spec. Sess.) (listing
covered occupations but not including law enforcement). Thus, we should
examine the language used when voters amended Section Eight to require
compensation for a broader group of workers, including law enforcement
officers. See Norino Props., LLC v. Balsamo, 265 A.3d 1109, 1125 (Md. Ct.
Spec. App. 2021) (noting that “[a]mendments to a constitutional provision
also ‘bear on the proper construction of the provision as it currently exists,’
and in such a situation, ‘the intent of the amenders . . . may become
paramount’” (quoting State v. Phillips, 179 A.3d 965, 969 (Md. 2018))).

¶63 That “injury” and “personal injury” include mental injuries
comes into sharper focus when considering their meaning in 1925, when
Section Eight was substantially amended. In 1925, the legislature repealed
the laws originally enacted to carry out Section Eight’s directive and
replaced it with a more robust workers’ compensation act. See 1925 Ariz.
Sess. Laws ch. 83 (Reg. Sess.). Among other things, the new act created the
industrial commission; established the state compensation fund; extended
benefits to more workers and their dependents; included death benefits;
and set wage percentages tied to disabilities to pay injured workers. See id.
Simultaneously, the legislature called a special election for voters to amend
Section Eight. See id. ch. 81–82. Unlike the 1912 version, the amended
Section Eight also applied to publicly employed workers engaged in non-
dangerous manual or mechanical labor; applied to privately employed
workers as designated by the legislature; required payment of death
benefits; declared that the wage percentages in the 1925 act could never be
reduced or eliminated; provided for a worker’s pre-injury election to accept
compensation or instead sue the employer; and made other changes. See
Ariz. Const. art. 18, § 8 (1925). The publicity pamphlet for the special
election generally described the proposed amendments but did not
separately identify the new language. See Ariz. Sec’y of State, 1925 Publicity

20
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

Pamphlet 516–17 (1925). Instead, voters were presented with the entire text
of the proposed new Section Eight, which interwove the new and old
language without distinction. See id. at 517–18.

¶64 Because the entirety of the new Section Eight was put before
voters in 1925, and voters necessarily applied their understanding of
“injury” and “personal injury” in deciding whether workers’ compensation
benefits should be extended to injuries suffered by public workers engaged
in non-dangerous jobs and to designated private workers, the meaning of
the language in 1925 is determinative. See Norino Props., 265 A.3d at 1125.4
The majority asserts that because “injury” and “personal injury” were used
in Section Eight’s amended version, the meaning assigned by 1912 voters
controls. See supra ¶ 40. But common sense dictates that voters in 1925 gave
their own meaning to “injury” and “personal injury” in deciding whether
to extend benefits without considering how their 1912 counterparts defined
the terms. See Salt River Project Agric. Improvement & Power Dist. v. Apache
Cnty., 172 Ariz. 337, 342 (1992) (“[N]o matter what result might be reached
by applying constructs contained in the various canons of statutory and
constitutional construction, common sense must also inform our
decision.”). Returning to the 1912 meaning of those words, assuming it
differed from the 1925 meaning, would metaphorically pull the rug from
beneath the 1925 voters’ feet and should not be tolerated. Consequently, it
would not be reasonable in those circumstances to ignore the ordinary
meaning of “injury” and “personal injury” in 1925 and instead invoke their
1912 meanings.

¶65 As previously explained, I conclude that “injury” and
“personal injury” included mental injuries in 1912. And by 1925, after
soldiers had experienced “shell shock” from their experiences in World
War I, people undoubtedly embraced this meaning. See, e.g., Sjoholm v.
Hercules Powder Co., 199 N.W. 603, 604–05 (Mich. 1924) (affirming workers’
compensation award to widow of worker who suffered a “mental and

4
The voters again amended Section Eight in 1980. See Ariz. Const. art. 18,
§ 8 (historical note). But that amendment did not concern the scope of
“injury” or “personal injury,” and interlineated language identified the new
provisions for voters. See 1980 Ariz. Sess. Laws H.C.R. No. 2013 (2d Reg.
Sess.). Thus, 1980 voters had no reason to ascribe new meaning to “injury”
and “personal injury,” and the meaning understood by 1925 voters remains
determinative. See Norino Props., 265 A.3d at 1125.
21
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

nervous condition” likened to “shell shock” caused by his presence during
a massive explosion at his job site); F. G. Fowler & H. W. Fowler, The Pocket
Oxford Dictionary of Current English 406 (4th ed. 1924) (defining “injury”
as “wrong; harm, damage”). The majority ignores Sjoholm, a case directly
on point concerning the issue here, and instead asserts that the dictionary
definition of “injury” and common usage of the term remained unchanged
since 1912. See supra ¶¶ 41–42.

¶66 In sum, I disagree with the majority that “injury” and
“personal injury” referred only to physical trauma in 1912. But even if that
were so, 1925 voters undoubtedly understood these terms as including
mental injuries, and the majority incorrectly ignores their viewpoint.

II. Defining “Accident”

¶67 Section Eight contains no language restricting “accident” to
mean an “unexpected event,” as the majority concludes. See supra ¶ 37. The
only limitation is that “any accident” must be caused wholly or partially by
(1) “a necessary risk or danger” of the job; or (2) a failure by the employer,
an employee, or an agent to exercise due care or follow employment laws.
See Ariz. Const. art. 18, § 8. This Court has consistently held that “any
accident” in our workers’ compensation laws includes an unexpected
resulting injury and is compensable if the other criteria are met. See, e.g.,
Fireman’s Fund Ins. Co. v. Indus. Comm’n, 119 Ariz. 51, 53 (1978) (“[A]n injury
is caused by accident when the resulting injury is unexpected.”); Paulley v.
Indus. Comm’n, 91 Ariz. 266, 272 (1962) (“[W]e again announce that Arizona
follows the English and now majority American view that an injury is
caused ‘by accident’ when either the external cause or the resulting injury
itself is unexpected or accidental. This construction of the phrase ‘injury by
accident’ is most likely to effectuate . . . the evident purpose of the law that
those covered by the act who are injured while engaged in industrial work
are to be compensated.’” (second alteration in original) (quoting Goodyear
Aircraft Corp. v. Indus. Comm’n, 62 Ariz. 398, 402 (1945))). Nothing in Section
Eight suggests we should give “accident” in that provision a different, more
restrictive meaning. Thus, giving the term its ordinary meaning, it
encompasses unexpected injuries even when caused by expected events.

¶68 The majority relies on the 1912 definition of “accident,” which
includes “mishap,” a word that fairly describes injuries resulting from
unexpected and expected events. See Laird & Lee’s Webster’s New
22
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

Standard American Dictionary of the English Language 726 (1911)
(defining “mishap” as “[i]ll-luck; misfortune”). This definition also applied
in 1925. See Fowler, supra ¶ 65, at 501 (defining “mishap” as “minor
calamity”). Thus, for example, if a miner in 1913 had broken his hand while
blasting rock, this would have constituted a “mishap” or “accident” even
though the blast itself was an expected event. Although the miner’s injury
was unexpected, it would have been compensable as arising from the
course of employment and caused by necessary risks or dangers of mining.
See Ariz. Const. art. 18, § 8. This is just the sort of injury Section Eight was
designed to address, yet the majority’s restrictive definition would
preclude compensation in this scenario.

¶69 The majority’s additional restriction of “accident” to
“singular” events is also incorrect, in my view, although this restriction
does not affect the disposition here. See supra ¶ 37. This Court has
consistently defined “accident” under the workers’ compensation laws as
including injuries gradually developing over time. See, e.g., Martinez v.
Indus. Comm’n, 192 Ariz. 176, 181 ¶ 23 (1998) (“We do not accept the notion
that one injury is compensable because it is caused by a single traumatic
event which aggravates a pre-existing condition, but another injury is not
compensable because employment activity that is repetitive gradually
aggravates a pre-existing condition.”). For example, a miner who breathed
noxious fumes while working from 1913 through 1920 and developed a
resulting lung disease would have suffered a “mishap” or “accident” even
though the fumes gradually caused the disease. Although the lung disease
was unexpected and developed gradually, it would have been compensable
as arising from the course of employment and caused by necessary risks or
dangers of mining. See Ariz. Const. art. 18, § 8. Again, this is just the sort
of injury Section Eight was designed to address, yet the majority’s
restrictive definition would preclude compensation in this scenario.

¶70 In sum, I conclude that an “accident” in Section Eight means
an unexpected event or an unexpected injury. I further conclude that job
conditions can constitute an “accident” when they gradually cause an
injury.

23
 MATTHEWS V. ICA/CITY OF TUCSON (TRISTAR)
VICE CHIEF JUSTICE TIMMER, Concurring in Part and Dissenting in
Part

III. Application Here

¶71 Because “injury” and “personal injury” in Section Eight
encompass mental injuries, and “accident” in that provision includes
unexpected injuries, the legislature is prohibited from excluding coverage
of mental injuries arising from job-related events “unless some unexpected,
unusual or extraordinary stress related to the employment or some physical
injury related to the employment was a substantial contributing cause.” See
§ 23-1043.01(B). This limitation impermissibly redefines legal causation as
set forth in Section Eight. See Grammatico v. Indus. Comm’n, 211 Ariz. 67, 72
¶ 23 (2005) (declaring a statute unconstitutional that altered Section Eight’s
legal causation requirement by excluding compensation for job accidents
“if alcohol or illegal drug use contributed even slightly to the accident”
caused by a necessary risk or danger of employment). 5

¶72 The majority complains that this conclusion transforms
Section Eight into a “general insurance coverage” provision that was never
intended by voters. See supra ¶ 47. That may be so. But voters’ unexpressed
intentions are neither here nor there. Our role is to identify the meaning of
the language used in Section Eight and apply it. See Randy E. Barnett, An
Originalism for Nonoriginalists, 45 Loy. L. Rev. 611, 622 (1999) (criticizing
some originalists for “still search[ing] for how the relevant generation of
ratifiers expected or intended their textual handiwork would be applied to
specific cases”). Curtailment of Section Eight should be through
amendment of that provision at the ballot box.

¶73 For all these reasons, I would set aside the Industrial
Commission’s decision and order.

5
Section 23-1043.01(B) also excludes compensation for mental injuries
caused by “some physical injury related to the employment” unless the
physical injury “was a substantial contributing cause of the mental injury,
illness or condition.” Whether this restriction concerns medical causation,
and is therefore permissible under Section Eight, is not before us. See
Grammatico, 211 Ariz. at 71-72 ¶ 20 (recognizing that Section Eight “does
not limit the legislature’s power to enact legislation affecting medical
causation”).
24