                  FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

GEORGE FIELDS, personal                 
representative of the Estate of
Laura Fields,
                 Plaintiff-Appellant,        No. 03-35386
                 v.                           D.C. No.
LEGACY HEALTH SYSTEM, an                    CV-03-00048-KI
Oregon Corporation, dba/Legacy
Laboratory Services.
                Defendant-Appellee.
                                        
        Appeal from the United States District Court
                 for the District of Oregon
          Garr M. King, District Judge, Presiding


GEORGE FIELDS, personal                 
representative of the Estate of
Laura Fields; ESTATE OF LAURA
FIELDS,                                      No. 03-35587
               Plaintiffs-Appellants,
                 v.                            D.C. No.
                                            CV-02-02548-TSZ
LEGACY HEALTH SYSTEM, an                       OPINION
Oregon Corporation, dba/Legacy
Laboratory Services.
                Defendant-Appellee.
                                        
        Appeal from the United States District Court
              for the District of Washington
         Thomas S. Zilly, District Judge, Presiding


                             7395
7396          FIELDS v. LEGACY HEALTH SYSTEM
                 Argued and Submitted
          September 14, 2004—Portland, Oregon

                    Filed June 22, 2005

       Before: Susan P. Graber, Ronald M. Gould, and
             Marsha S. Berzon, Circuit Judges.

                Opinion by Judge Gould;
               Concurrence by Judge Gould
              FIELDS v. LEGACY HEALTH SYSTEM           7399


                        COUNSEL

Ron Perey, Carla Tachau Lawrence, and Doug Weinmaster,
Law Office of Ron Perey, Seattle, Washington, and Jeffrey P.
Foote, Portland, Oregon, for the plaintiff-appellant.
7400            FIELDS v. LEGACY HEALTH SYSTEM
Lindsey H. Hughes, Keating Jones Bildstein & Hughes, P.C.,
Portland, Oregon, for the defendant-appellee.


                            OPINION

GOULD, Circuit Judge:

   This consolidated appeal involves wrongful death actions
filed in two different federal district courts sitting in diversity.
Acting as personal representative of the estate of his late wife,
Laura Fields, George Fields brought an action for wrongful
death against Legacy Health System (“Legacy”) in the United
States District Court for the Western District of Washington.
The complaint alleged that Legacy negligently caused Laura
Fields’ death by failing to diagnose her cervical cancer from
a Pap smear, and sought damages for Raven Fields, a minor
child of George and Laura Fields. Subsequently, George
Fields filed an identical action in the United States District
Court for the District of Oregon. The Oregon federal district
court applied Oregon’s statutes of limitations and repose to
dismiss George Fields’ case with prejudice, denied him leave
to amend his complaint, and denied his motion to certify state
constitutional questions to the Oregon Supreme Court. There-
after, the Washington federal district court dismissed George
Fields’ Washington action based on Oregon’s statutes of limi-
tations and repose, as well as on collateral estoppel grounds.

   George Fields appeals these rulings. He first contends that
the district courts erred in applying Oregon law instead of
Washington law. In the alternative, he argues that if Oregon
law applies, we should either: (1) apply Oregon’s disability
tolling provision to toll Oregon’s wrongful death statute of
limitations; (2) apply the “escape clause” in the Uniform Con-
flict of Laws-Limitations Act (“UCLLA”) to allow his Wash-
ington suit to proceed; (3) strike down Oregon’s statutes of
limitations and repose because they violate the United States
                 FIELDS v. LEGACY HEALTH SYSTEM                   7401
Constitution; or (4) certify to the Oregon Supreme Court
whether Oregon’s statutes of limitations and repose violate
the state constitution.

   We have jurisdiction pursuant to 28 U.S.C. § 1291. We
affirm the district courts’ choice of Oregon law and reject
George Fields’ contentions that we can toll Oregon’s wrong-
ful death statute of limitations or apply the UCLLA’s “escape
clause” to permit his Washington suit to go forward. We also
hold that the Oregon statutes of limitations and repose do not
violate the United States Constitution or the Oregon Constitu-
tion.1

                                   I

   On August 3, 1994, Laura Fields had a Pap smear collected
and analyzed at the Legacy Good Samaritan Hospital in Port-
land, Oregon. Defendant-appellee Legacy is the non-profit
corporation that owns this hospital. On August 4, 1994, a hos-
pital employee analyzed Laura Fields’ Pap smear and con-
cluded that it was “Within Normal Limits. Negative.” The
employee also noted that Laura Fields was pregnant. Raven
Fields was born on March 19, 1995.

   In 1995, the Fields family moved to Washington. On
March 4, 1996, Laura Fields had another Pap smear and cervi-
cal biopsy. These procedures showed that she had cervical
cancer. In 1997, Laura and George Fields filed a negligence
claim against Legacy in the Circuit Court for the State of Ore-
gon, and the parties eventually reached a settlement agree-
ment whereby damages were paid in exchange for Laura and
  1
   Because we affirm the Oregon district court’s dismissal of George
Fields’ wrongful death suit, George Fields’ claim that he is entitled to
amend his complaint without leave under Federal Rule of Civil Procedure
15(a) is moot.
7402                FIELDS v. LEGACY HEALTH SYSTEM
George Fields’ release of “any and all claims” on behalf of
themselves and their “heirs, executors and assigns.”2

  Laura Fields died on January 16, 2000, while a resident of
Washington. Acting as personal representative of Laura
Fields’ estate, George Fields brought a diversity action
against Legacy for wrongful death, bringing suit in the United
States District Court for the Western District of Washington
on December 23, 2002. He also filed an identical action in the
United States District Court for the District of Oregon on Jan-
uary 13, 2003. Legacy moved to dismiss the Oregon action
pursuant to Federal Rule of Civil Procedure 12(b)(6), and the
Oregon federal district court granted its motion, dismissing
George Fields’ claim with prejudice on the ground that the
suit was barred by Oregon’s statute of limitations3 and also
  2
    Neither of the federal district courts addressed the scope of the release
contained in this settlement agreement because they disposed of George
Fields’ actions based on Oregon’s statutes of limitations and repose.
  3
    Oregon Revised Statutes § 30.020(1), provides:
      When the death of a person is caused by the wrongful act or
      omission of another, the personal representative of the decedent,
      for the benefit of the decedent’s surviving spouse [or] surviving
      children . . . may maintain an action against the wrongdoer, if the
      decedent might have maintained an action, had the decedent
      lived, against the wrongdoer for an injury done by the same act
      or omission. The action shall be commenced within three years
      after the injury causing the death of the decedent is discovered or
      reasonably should have been discovered by the decedent, by the
      personal representative or by a person for whose benefit the
      action may be brought under this section if that person is not the
      wrongdoer. In no case may an action be commenced later than
      the earliest of:
          (a)   Three years after the death of the decedent; or
          (b) The longest of any other period for commencing an
          action under a statute of ultimate repose that applies to the
          act or omission causing the injury, including but not limited
          to the statutes of ultimate repose provided for in ORS
          12.110(4), 12.115, 12.135, 12.137 and 30.905.
                  FIELDS v. LEGACY HEALTH SYSTEM                      7403
was barred by Oregon’s statute of repose.4 The Washington
federal district court decision followed, applying Oregon’s
statute of limitations and Oregon’s statute of repose to dismiss
George Fields’ Washington action with prejudice. George
Fields timely appealed the dismissals from both of the federal
district courts, and we consolidated the cases for the purposes
of appellate review because of the parallel issues.

                                    II

   [1] We first address George Fields’ argument that the dis-
trict courts erred in applying Oregon’s statutes of limitations
and repose to dismiss his claims because, he argues, “Wash-
ington has by far the most compelling interest in having its
wrongful death statute applied to this case.” Federal courts sit-
ting in diversity must apply “the forum state’s choice of law
rules to determine the controlling substantive law.” Patton v.
Cox, 276 F.3d 493, 495 (9th Cir. 2002).5 Although the Oregon
  4
    The Oregon medical malpractice statute of ultimate repose, Or. Rev.
Stat. § 12.110(4), provides:
    An action to recover damages for injuries to the person arising
    from any medical . . . treatment, omission or operation shall be
    commenced within two years from the date when the injury is
    first discovered or in the exercise of reasonable care should have
    been discovered. However, notwithstanding the provisions of
    ORS 12.160 [the disability tolling statute], every [malpractice
    action] shall be commenced within five years from the date of
    treatment, omission or operation upon which the action is based
    ....
This five-year repose period is absolute in the absence of fraud, deceit, or
a misleading representation, for which a statutory exception applies. Urb-
ick v. Suburban Med. Clinic, Inc., 918 P.2d 453, 455-56 (Or. Ct. App.
1996). It does not matter when the claim accrued, or even if it has accrued.
Id. at 457.
   5
     A dismissal for failure to state a claim pursuant to Federal Rule of
Civil Procedure 12(b)(6) is reviewed de novo. Libas Ltd. v. Carillo, 329
F.3d 1128, 1130 (9th Cir. 2003). All allegations of material fact are taken
as true and viewed in the light most favorable to the non-movant. Nat’l
7404              FIELDS v. LEGACY HEALTH SYSTEM
district court relied on grounds that we find unpersuasive, we
affirm its decision to apply Oregon law because our choice of
law analysis under Oregon law leads us to the same conclu-
sion that Oregon law governs. We agree with the Washington
district court’s analysis and affirm its choice of Oregon law.

   Oregon and Washington use the same bifurcated approach
in dealing with conflict of law issues. Both states’ laws
require us to make a threshold determination that there is an
actual conflict between the law of the forum and that of
another state. Portland Trailer & Equip., Inc. v. A-1 Freeman
Moving & Storage, Inc., 49 P.3d 803, 806 (Or. Ct. App.
2002); Rice v. Dow Chem. Co., 875 P.2d 1213, 1216 (Wash.
1994). If no material conflict exists between the laws or inter-
ests of the forum and the other state, we apply forum law.
Portland Trailer, 49 P.3d at 806; Rice, 875 P.2d at 1216. If
there is a conflict, we proceed to the next step of the analysis
and apply the forum’s choice of law test. Portland Trailer, 49
P.3d at 809; Rice, 875 P.2d at 1217.

  The parties here identified a conflict between Washington
and Oregon’s wrongful death statutes of limitations.6 The

Ass’n for the Advancement of Psychoanalysis v. Cal. Bd., 228 F.3d 1043,
1049 (9th Cir. 2000). However, “[c]onclusory allegations of law and
unwarranted inferences are insufficient to defeat a motion to dismiss for
failure to state a claim.” Id.
   We review de novo a district court’s choice of law decisions, Abogados
v. AT&T, Inc., 223 F.3d 932, 934 (9th Cir. 2000), as well as its interpreta-
tions of state law, Feature Realty, Inc. v. City of Spokane, 331 F.3d 1082,
1086 n.3 (9th Cir. 2003).
   6
     Oregon requires wrongful death actions to be brought within three
years from the date the injury causing death is discovered or reasonably
should have been discovered. Or. Rev. Stat. § 30.020(1). On the other
hand, Washington allows wrongful death actions based on medical mal-
practice claims to be brought within three years of the date of death. Wills
v. Kirkpatrick, 785 P.2d 834, 837 (Wash. Ct. App. 1990) (holding that
general statute of limitations in Wash. Rev. Code § 4.16.080(2) applies in
wrongful death cases based on medical malpractice instead of the medical
malpractice statute of limitations, Wash. Rev. Code § 4.16.350, because
legislature did not intend to bar claims even before death triggered accrual
of right to bring action); see also Wash. Rev. Code § 4.16.080(2).
                FIELDS v. LEGACY HEALTH SYSTEM               7405
Oregon district court accepted this conflict as one that satis-
fied the threshold requirement under Oregon’s choice of law
rules and proceeded to apply Oregon’s choice of law test. The
Washington district court, however, identified a conflict
between the states’ statutes of repose and conducted its choice
of law analysis from that starting point.

   [2] The Oregon district court erred in determining that a
difference between Oregon’s statute of limitations and that of
another state can raise an actual conflict for the purposes of
Oregon’s choice of law analysis. Oregon, like Washington,
has adopted the UCLLA, which states in pertinent part:

    (1) Except as provided by ORS 12.450, if a claim
    is substantively based:

    (a) Upon the law of one other state, the limitation
    period of that state applies; or

    (b) Upon the law of more than one state, the limita-
    tion period of one of those states, chosen by the law
    of conflict of laws of this state, applies.

    (2) The limitation period of this state applies to all
    other claims.

Or. Rev. Stat. § 12.430; see also Wash. Rev. Code § 4.18.020
(same). Under this provision, the initial determination courts
must make in cases involving disputes over the relevant stat-
ute of limitations is which state’s substantive law forms the
basis of the plaintiff’s claims. Cropp v. Interstate Distrib. Co.,
880 P.2d 464, 465 (Or. Ct. App. 1994); Rice, 875 P.2d at
1216. Once the court decides which state’s substantive law
governs, that state’s statute of limitations applies. Cropp, 880
P.2d at 465; Rice, 875 P.2d at 1216. In other words, UCLLA
states like Washington and Oregon treat statutes of limitations
as procedural for the purposes of conflict of law analyses.
7406               FIELDS v. LEGACY HEALTH SYSTEM
   [3] On the other hand, Washington treats statutes of repose
“as part of the body of a state’s substantive law in making
choice-of-law determinations.”7 Rice, 875 P.2d at 1217. Here,
Oregon has a statute of repose that extinguishes all actions
based on a claim of medical malpractice that are not brought
within “five years from the date of the treatment, omission or
operation upon which the action is based.” Or. Rev. Stat.
§ 12.110(4). In DeYoung v. Providence Medical Center, 960
P.2d 919, 926 (Wash. 1998), however, the Washington State
Supreme Court invalidated Washington’s medical malpractice
statute of repose. Because Oregon has an applicable statute of
repose while Washington does not, there is a valid conflict
between Oregon and Washington law that requires us to apply
Washington’s choice of law test. See Rice, 875 P.2d at 1217.

   Oregon has yet to decide whether statutes of repose are
substantive or procedural, but this does not affect our holding
that Oregon law governs George Fields’ Oregon action. If, as
seems likely, the Oregon Supreme Court would consider Ore-
gon’s statutes of repose to be substantive,8 then application of
  7
     Although the distinction between statutes of limitations and statutes of
repose is often blurred, statutes of limitations differ from statutes of repose
because the former “bars plaintiff[s] from bringing an already accrued
claim after a specified period of time,” whereas the latter “terminates a
right of action after a specific time, even if the injury has not yet
occurred.” Rice, 875 P.2d at 1216.
   8
     The general weight of authority accepts the characterization of statutes
of repose as substantive provisions in a choice of law context. See, e.g.,
Goad v. Celotex Corp., 831 F.2d 508, 511 (4th Cir. 1987); Wayne v. Tenn.
Valley Auth., 730 F.2d 392, 401-02 (5th Cir. 1984); Pottratz v. Davis, 588
F. Supp. 949, 952-53 (D. Md. 1984); Nieman v. Press & Equip. Sales Co.,
588 F. Supp. 650, 653 (S.D. Ohio 1984); Berns Constr. Co. v. Miller, 491
N.E.2d 565, 570 (Ind. Ct. App. 1986), aff’d 516 N.E.2d 1053 (Ind. 1987);
Harris v. Clinton Corn Processing Co., 360 N.W.2d 812, 816-17 (Iowa
1985); Boudreau v. Baughman, 368 S.E.2d 849, 857 (N.C. 1988);
DePaolo v. Dep’t of Pub. Welfare, 865 A.2d 299, 305 n.7 (Pa. Commw.
Ct. 2005); Rice, 875 P.2d at 1217.
                  FIELDS v. LEGACY HEALTH SYSTEM                     7407
Oregon’s choice of law test will lead to the conclusion that an
Oregon court would apply Oregon law to the present case.9

   Oregon and Washington both follow the Restatement (Sec-
ond) of Conflict of Laws § 145 (1971) approach for determin-
ing what substantive law should apply in tort cases. DeFoor
v. Lematta, 437 P.2d 107, 108 n.5 (Or. 1968); Rice, 875 P.2d
at 1217. Under the Restatement, a court should consider the
following contacts to determine which state has “the most sig-
nificant relationship” to the case: (a) the place where the
injury occurred; (b) the place where the conduct causing the
injury occurred; (c) the domicile, residence, nationality, place
of incorporation and place of business of the parties; and (d)
the place where the relationship, if any, between the parties is
centered. Restatement (Second) of Conflict of Laws § 145.

   [4] Here, Oregon has the most significant contacts. The
injury in this case was Laura Fields’ misdiagnosis and inabil-
ity to seek treatment, not her resulting death. The conduct
causing the injury was Legacy’s negligence in analyzing
Laura Fields’ pap smear, and this also occurred in Oregon.
Legacy is an Oregon corporation that maintains its principal
place of business in Oregon. Laura Fields was an Oregon resi-
dent when she sustained her injury of misdiagnosis, although
she subsequently became a Washington resident and died
leaving beneficiaries who are Washington residents. Finally,
the relationship between Laura Fields and Legacy existed in
Oregon while Laura Fields was undergoing treatment at Lega-
cy’s hospital. In sum, Washington has a few significant con-
tacts with this case, but they are less significant than Oregon’s
contacts.
  9
   If the Oregon State Supreme Court were to decide that statutes of
repose are procedural, then Oregon’s choice of law rules would lead to the
same result, because “Oregon courts resolve procedural issues under Ore-
gon law” in the conflict of laws context. Manz v. Cont’l Am. Life Ins. Co.,
843 P.2d 480, 481 (Or. Ct. App. 1993).
7408            FIELDS v. LEGACY HEALTH SYSTEM
   Also relevant to the Restatement’s choice of law analysis
is a determination of each state’s interest in having its law
apply. DeFoor, 437 P.2d at 109-10; Johnson v. Spider Staging
Corp., 555 P.2d 997, 1001-02 (Wash. 1976). George Fields
contends that Washington’s interest in seeing its residents
compensated for an allegedly wrongful death is paramount.
However, as both district courts noted, the Washington State
Supreme Court has previously held that Washington’s interest
in seeing its residents compensated for injuries is not overrid-
ing where other contacts with Washington are minimal. Rice,
875 P.2d at 1218-19; see also Restatement (Second) of Con-
flict of Laws § 145 cmt. e (“that one of the parties is domi-
ciled . . . in a given state will usually carry little weight of
itself”).

   Rice is factually similar to this case: The plaintiff in Rice
was diagnosed, while residing in Washington, with leukemia
allegedly caused by his exposure to hazardous chemicals
manufactured and sold by the defendant while he was work-
ing in Oregon. The Washington State Supreme Court applied
Oregon’s product liability statutes of limitations and repose to
dismiss the action because the mere fact of residency in
Washington alone was insufficient to warrant application of
Washington law where the plaintiff’s move to Washington did
not extinguish Oregon’s significant interest in allegedly dan-
gerous products used within its boundaries. Rice, 875 P.2d at
1217-19. Moreover, the application of Oregon law achieved
a uniform result for injuries caused by products used within
the state and provided predictability for manufacturers whose
products are used in Oregon. Id. at 1219.

   [5] The same reasoning applies here. Oregon has a clear
interest in the standard of medical care within its boundaries.
Oregon has the ability to regulate the medical industry in the
state. It also has an interest in protecting its medical providers
from stale claims and the excessive financial burdens of liti-
gating wrongful death claims. See, e.g., Johnson, 555 P.2d at
1002. We hold that Oregon’s statutes of repose and limita-
                     FIELDS v. LEGACY HEALTH SYSTEM                     7409
tions apply to George Fields’ claim whether brought in Ore-
gon or Washington.

                                      III

   [6] Having concluded that Oregon law applies to both the
Oregon and Washington actions, we next consider George
Fields’ argument that Oregon’s statutes of limitations and
repose do not bar the claim he is bringing on behalf of his
child because “the anti-tolling provision in ORS 12.110(4) . . .
is not incorporated into ORS 30.020.” We reject this argu-
ment because the statutory text does not permit the interpreta-
tion urged by George Fields. Oregon Revised Statutes section
30.020(1)(b) expressly incorporates section 12.110(4), the
medical malpractice statute of repose, which in turn expressly
prohibits the use of the disability tolling statute, section 12.160.10

   [7] Moreover, the plain language of the disability tolling
statute, section 12.160,11 limits its application to “action[s]
  10
    Section 30.020(1) provides in pertinent part: “In no case may an
action be commenced later than the earliest of: (a) Three years after the
death of the decedent; or (b) The longest of any other period for com-
mencing an action under a statute of ultimate repose that applies to the act
or omission causing the injury, including but not limited to the statutes of
ultimate repose provided for in ORS 12.110(4) . . . .”
   Section 12.110(4) provides in pertinent part that, “notwithstanding the
provisions of ORS 12.160 [the disability tolling statute], every [malprac-
tice] action shall be commenced within five years from the date of the
treatment, omission or operation upon which the action is based.”
   11
      The full text of Section 12.160 reads:
       If, at the time the cause of action accrues, any person entitled to
       bring an action mentioned in ORS 12.010 to 12.050, 12.070 to
       12.250 and 12.276 is within the age of 18 years or insane, the
       time of such disability shall not be a part of the time limited for
       the commencement of the action; but the period within which the
       action shall be brought shall not be extended more than five years
       by any such disability, nor shall it be extended in any case longer
       than one year after such disability ceases.
7410            FIELDS v. LEGACY HEALTH SYSTEM
mentioned in ORS 12.010 to 12.050, 12.070 to 12.250 and
12.276.” See also Stupek v. Wyle Labs. Corp., 963 P.2d 678,
685 (Or. 1998) (holding that courts lacked authority to toll
statutory discrimination claim for insanity where the claim
was not enumerated in section 12.160 and anti-discrimination
statute did not otherwise provide for tolling). The actions here
appealed fall under Oregon’s wrongful death statute, section
30.020, which is clearly not within the statutory ranges listed
in section 12.160. Thus, we decline to apply section 12.160 to
toll George Fields’ wrongful death action.

                               IV

  George Fields also contends that, if we apply Oregon law,
we should follow the “escape clause” provision in the
UCLLA to allow his Washington case to go forward under
Washington’s statute of limitations.

   [8] As noted above, Washington has adopted the UCLLA.
Wash. Rev. Code §§ 4.18.010-.904. Section 4 of the UCLLA,
which is codified at Washington Revised Code section
4.18.040, provides:

    If the court determines that the limitation period of
    another state applicable under [the Washington con-
    flict of law borrowing statute and limitation period
    computation rules] is substantially different from the
    limitation period of this state and has not afforded a
    fair opportunity to sue upon, or imposes an unfair
    burden in defending against, the claim, the limitation
    period of this state applies.

This provision is an “escape clause,” allowing a court to eval-
uate the disparate effect of a foreign statute of limitations and
choose to apply a local limitations period to avoid unfairness.
Hein v. Taco Bell, Inc., 803 P.2d 329, 333-34 (Wash. Ct. App.
1991).
                FIELDS v. LEGACY HEALTH SYSTEM               7411
   [9] Application of this “escape clause” to permit George
Fields to avoid the Oregon statute of limitations does not
resolve George Fields’ problem because his claim would still
be barred by Oregon’s statute of repose. In other words,
George Fields has to circumvent both Oregon’s statute of lim-
itations and its statute of repose in order to continue his action
in the Washington district court, but the language of the “es-
cape clause” covers only limitations periods and the Washing-
ton State Supreme Court expressly held in Rice, 875 P.2d at
1217, that statutes of repose are not the same as statutes of
limitations for conflicts of law purposes. We conclude that
George Fields’ claim is time-barred by the statute of repose
under Oregon law, notwithstanding the UCLLA’s “escape
clause.”

                                V

  We now address George Fields’ assertion that Oregon’s
wrongful death statutes of limitations and repose violate the
equal protection and due process clauses of the United States
Constitution.

                                1

   George Fields argues that the Oregon wrongful death stat-
utes of limitations and repose violate equal protection because
they impermissibly discriminate between claimants whose
decedents happen to live for more than three years after dis-
covering the injury causing the death and five years of sus-
taining the injury causing death, as in Laura’s case, and
claimants whose decedents die within three years of discover-
ing the injury causing death and five years of sustaining the
injury causing death.

   [10] The appropriate level of equal protection review in this
case is the “rational basis test,” which applies to challenges of
legislative acts that neither affect the exercise of fundamental
rights, nor classify persons based on protected characteristics,
7412            FIELDS v. LEGACY HEALTH SYSTEM
such as race, alienage, national origin, or sex. See, e.g.,
Silveira v. Lockyer, 312 F.3d 1052, 1088 (9th Cir.), cert.
denied, 540 U.S. 1046 (2003). Under this test, statutes are
generally “presumed to be valid and will be sustained if the
classification drawn by the statute is rationally related to a
legitimate state interest.” Id. (quoting City of Cleburne v. Cle-
burne Living Ctr., 473 U.S. 432, 440 (1985)). In essence, a
legislative classification subject to rational basis scrutiny
“must be ‘wholly irrational’ to violate equal protection.” De
Martinez v. Ashcroft, 374 F.3d 759, 764 (9th Cir. 2004). The
challenger bears the burden of negating every conceivable
basis which might support the legislative classification,
whether or not the basis has a foundation in the record. Id.

   [11] Here, the classifications made in the Oregon statutes
of limitations and repose are rationally related to the legiti-
mate legislative ends of avoiding stale claims and limiting the
costs of litigation and medical care. See Jones v. Salem Hosp.,
762 P.2d 303, 309 (Or. Ct. App. 1988) (noting that Oregon’s
medical malpractice repose statute was “enacted in response
to the so called ‘medical malpractice crisis’ ”). The statutes at
issue here withstand equal protection scrutiny under the
United States Constitution. See Nored v. Blehm, 743 F.2d
1386, 1387 (9th Cir. 1984) (per curiam) (upholding the con-
stitutionality of a similar Oregon statute of limitations in the
face of an equal protection challenge); Sealey v. Hicks, 788
P.2d 435, 441 (Or. 1990) (holding that similar Oregon product
liability statute of repose does not violate federal equal pro-
tection clause), abrogated on other grounds by Smothers v.
Gresham Transfer Inc., 23 P.3d 333 (Or. 2001).

                               2

   George Fields further argues that the Oregon statutes of
limitations and repose violate the substantive and procedural
aspects of the due process clause of the United States Consti-
tution. These claims must fail.
                FIELDS v. LEGACY HEALTH SYSTEM              7413
   [12] First, for the purposes of substantive due process
review, state actions that implicate anything less than a funda-
mental right require only that the government demonstrate “a
reasonable relation to a legitimate state interest to justify the
action.” Doe v. Tandeske, 361 F.3d 594, 597 (9th Cir. 2004)
(per curiam), cert. denied, 125 S. Ct 56 (2004) (quoting
Washington v. Glucksberg, 521 U.S. 702, 722 (1997). This is
the appropriate standard of review for this case as Oregon’s
wrongful death statutes do not implicate any of the “personal
activities and decisions” the Supreme Court has identified as
being “deeply rooted in our history and traditions” or “funda-
mental to our concept of constitutionally ordered liberty.” Id.
at 596 (citing Glucksberg, 521 U.S. at 727 & n.19, which
listed marriage, family association, and procreation as funda-
mental activities).

   [13] Applying this deferential standard of review, we con-
clude that Oregon’s statutes of limitations and repose do not
violate George Fields’ rights to substantive due process
because, as explained above, the statutes are rationally related
to the legitimate legislative goals of avoiding stale claims and
limiting the costs of litigation and malpractice claims.

   [14] We reach the same result under a procedural due pro-
cess analysis. Although his briefing is unclear on this point,
it appears that George Fields’ procedural due process argu-
ment rests on the theory that he has been deprived of a prop-
erty right in his “remedy” or cause of action without due
process of law.

  Causes of action are a species of property protected by the
Fourteenth Amendment’s Due Process Clause. Lyon v. Agusta
S.P.A., 252 F.3d 1078, 1086 (9th Cir. 2001); Zavala v. United
States, 876 F.2d 780, 784 (9th Cir. 1989); Austin v. City of
Bisbee, 855 F.2d 1429, 1435 (9th Cir. 1988). However, “a
party’s property right in any cause of action does not vest
until a final unreviewable judgment is obtained.” Lyon, 252
F.3d at 1086; see also Austin, 855 F.2d at 1436 (explaining
7414            FIELDS v. LEGACY HEALTH SYSTEM
that, although a cause of action is a species of property, “it is
inchoate and affords no definite or enforceable property right
until reduced to final judgment”). Thus we previously rejected
similar procedural due process challenges to statutes cutting
off the right to sue on this ground. See, e.g., Austin, 855 F.2d
at 1436 (holding that retroactive application of amendments
to bar plaintiff from pursuing suit commenced prior to effec-
tive date of amendments did not violate procedural due pro-
cess because plaintiff had not yet obtained a final judgment).

   Moreover, even assuming that George Fields has a cogniza-
ble property right in his cause of action, his procedural due
process challenge fails because it is well established that the
legislature can adjust the benefits and burdens of our eco-
nomic lives as long as it does not behave in an arbitrary and
irrational way. Lyon, 252 F.3d at 1086; Austin, 855 F.2d at
1436 (explaining that economic legislation “come[s] to the
Court with a presumption of constitutionality, and . . . the bur-
den is on [the complainant] to establish that the legislature has
acted in an arbitrary and irrational way”).

   [15] We have upheld statutes of repose where we deter-
mined that the legislature was pursuing a rational policy in
enacting them. Lyon, 252 F.3d at 1086 (holding that retroac-
tively applying repose statute to cut off claims that accrued
before its enactment did not violate procedural due process
because legislature was acting to further rational goal of revi-
talizing flagging aircraft industry). The Oregon statute of ulti-
mate repose, Oregon Revised Statutes section 12.110(4), was
a rational legislative response to the medical malpractice cri-
sis and to the problem of stale claims. Accordingly, we sus-
tain it in the face of George Fields’ procedural due process
challenge.

   [16] Courts will generally uphold a statute of limitations
against a due process challenge as long as the plaintiff is
accorded a reasonable time, under all the circumstances, to
bring suit before the bar takes effect. See, e.g., Wheeler v.
                     FIELDS v. LEGACY HEALTH SYSTEM                        7415
Jackson, 137 U.S. 245, 255-58 (1890) (holding that statute
authorizing cancellation of realty sales records where pur-
chaser failed to compel conveyance within eight years did not
deprive the purchaser of property rights because purchaser’s
“property” was right to conveyance, and cancellation under
such circumstances was simply a reasonable limitation
imposed on enforcement of that right12); Brackney v. Combus-
tion Eng’g, Inc., 674 F.2d 812, 815 (9th Cir. 1982) (rejecting
due process challenge to retroactive application of state stat-
ute limiting tolling for disability to six years to bar cause of
action which accrued prior to its effective date); Pittman v.
United States, 341 F.2d 739, 741 (9th Cir. 1965) (holding that
application of two-year limitations period to minor’s claim
did not violate due process even though minor had no guard-
ian ad litem at the time the period ran).

   Here, the challenged statute of limitations, Oregon Revised
Statutes section 30.020(1), provides that wrongful death
actions must be brought within three years of the date the
injury causing death was discovered. Since Laura Fields’ mis-
diagnosis was discovered on March 4, 1996, George Fields
would have had to file this action by March 4, 1999, in order
to avoid the statute of limitations bar. The problem, of course,
as George Fields has pointed out, is that in this case, the stat-
ute of limitations eliminated his right to bring this wrongful
death suit even before Laura Fields died on January 16, 2000.
Consequently, George Fields characterizes Oregon’s wrongful
death scheme as “nonsensical” and “irrational” because it “re-
  12
    In so holding, the Supreme Court stated:
       It is the settled doctrine of this court that the legislature may pre-
       scribe a limitation for the bringing of suits where none previously
       existed, as well as shorten the time within which suits to enforce
       existing causes of action may be commenced, provided, in each
       case, a reasonable time, taking all the circumstances into consid-
       eration, be given by the new law for the commencement of suit
       before the bar takes effect.
Wheeler, 137 U.S. at 255.
7416             FIELDS v. LEGACY HEALTH SYSTEM
wards beneficiaries of the injured person who dies within the
statute of limitations . . . while harming the hopeful beneficia-
ries of an injured person who [can]not file a claim before the
injured person dies.” However, we are not persuaded.

   Section 30.020(1) provides a remedy for a decedent’s bene-
ficiaries only “if the decedent might have maintained an
action, had the decedent lived, against the wrongdoer for an
injury done by the same act or omission.” As the Oregon
Supreme Court explained in Storm v. McClung, it essentially
places a decedent’s personal representative in the decedent’s
shoes, imputing to the representative whatever rights and lim-
itations to those rights the decedent himself possessed. 47
P.3d 476, 482 (Or. 2002) (holding that beneficiaries of volun-
teer killed while working for city were barred from bringing
a wrongful death action because the accident was already cov-
ered by Oregon’s workers’ compensation law and there was
a statute immunizing public bodies from liability for such
covered claims that would have precluded the volunteer him-
self from suing the city for negligence). In other words,
because “ORS 30.020(1), by its own terms, does not give a
decedent’s personal representative a right to sue [a tortfeasor]
for negligent wrongful death when the decedent never had
that right in the first place,” a beneficiary’s wrongful death
action under Oregon Revised Statutes section 30.020(1) is
derivative of the decedent’s right to sue for the same injury
when alive. Id. at 481.

   [17] Given that Oregon’s wrongful death statute is intended
to allow beneficiaries to recover only the compensation that
was otherwise due the decedent, the fact that the statute of
limitations eliminated George Fields’ wrongful death claims
as a representative of the estate of Laura Fields, even before
they accrued does not lead to an unusually “harsh” result in
this case because Laura Fields already lived long enough to
bring suit herself and recover a settlement award.13 In light of
  13
   George Fields errs in maintaining that we cannot consider the settle-
ment agreement because the district courts declined to do so and because
                  FIELDS v. LEGACY HEALTH SYSTEM                      7417
Storm we hold that the Oregon statute of limitations was rea-
sonable as applied in this case.

                                    VI

   [18] We finally consider George Fields’ request that we
certify to the Oregon Supreme Court the questions whether
Oregon’s wrongful death scheme violates the Oregon Consti-
tution’s remedy clause and its privileges and immunities
clause. We decline to exercise our discretion to certify these
questions because “controlling precedent,” Or. Rev. Stat.
§ 28.200, is available to guide us. See W. Helicopter Servs.,
Inc. v. Rogerson Aircraft Corp., 811 P.2d 627, 631 (Or. 1991)
(explaining that the existence of controlling Oregon precedent
for a certified question is one of the most important factors
militating against the Oregon Supreme Court’s discretionary
acceptance of the certified question); see also Kremen v.
Cohen, 325 F.3d 1035, 1037-38 (9th Cir. 2003) (noting that
we have discretion whether to certify a question of state law

it is extrinsic to the complaint. We can affirm a dismissal for failure to
state a claim on any proper ground supported by the record even if the dis-
trict court did not consider the issue. Ove v. Gwinn, 264 F.3d 817, 821 (9th
Cir. 2001). Additionally, while our review of a 12(b)(6) dismissal is gener-
ally limited to the contents of the complaint, Gilligan v. Jamco Dev.
Corp., 108 F.3d 246, 248 (9th Cir. 1997), we can consider an extrinsic
document if it is integral to the plaintiff’s claims and its authenticity is
undisputed, because in such cases the plaintiff “obviously is on notice of
the contents of the document and the need for a chance to refute evidence
is greatly diminished.” Parrino v. FHP, Inc., 146 F.3d 699, 706 & n.4 (9th
Cir. 1998) (holding that it was permissible for district court entertaining
12(b)(6) motion to consider group insurance application offered by defen-
dant in action alleging improper denial of benefits). Thus we can consider
the settlement agreement as demonstrating that Laura Fields had a reason-
able time to bring suit on the injury, as she in fact did so and gained some
recovery. However, we decline to interpret in the first instance the scope
of the release entered by the parties by their settlement agreement of Janu-
ary 9, 1998; the scope of the release has never been addressed by either
federal district court, and we consider the record inadequate for our con-
clusive interpretation of the release.
7418            FIELDS v. LEGACY HEALTH SYSTEM
and that the “certification procedure is reserved for state law
questions that present significant issues . . . and that have not
yet been resolved by the state courts”).

   George Fields contends that Oregon’s wrongful death stat-
ute of limitations, Or. Rev. Stat. § 30.020, and medical mal-
practice statute of repose, Or. Rev. Stat. § 12.110(4), violate
the state constitution’s remedy clause, which provides that
“every man shall have remedy by due course of law for injury
done him in his person, property, or reputation.” Or. Const.
art. I, § 10.

   George Fields’ key assertions with respect to his remedy
clause claim are that wrongful death actions existed in Oregon
at common law at the time the state constitution was adopted
in 1857 and that the state legislature lacks the authority to
deny a remedy for injury to the kinds of rights that existed
then. Two lines of controlling Oregon precedent dictate that,
under current law, we must reject George Fields’ assertions.

   First, the Oregon Supreme Court has held repeatedly that,
in Oregon, the right of action for wrongful death is purely
statutory and that in Oregon there was no right of action for
wrongful death at common law. Storm, 47 P.3d at 479-82;
Smothers, 23 P.3d at 358; Lakin v. Senco Prods., Inc., 987
P.2d 463, 472 (Or.), op. clarified by 987 P.2d 476 (Or. 1999);
Kilminster v. Day Mgmt. Corp., 919 P.2d 474, 479 (Or.
1996); Greist v. Phillips, 906 P.2d 789, 796 (Or. 1995);
Hughes v. White (In re Estate of White), 609 P.2d 365, 368
(Or. 1980); Goheen v. Gen. Motors Corp., 502 P.2d 223, 226
(Or. 1972); Richard v. Slate, 396 P.2d 900, 901 (Or. 1964),
superseded by statute on other grounds as stated in Rennie v.
Pozzi, 656 P.2d 934, 938 (Or. 1982); see also Perham v. Port-
land Gen. Elec. Co., 53 P. 14, 18 (Or. 1898) (recognizing that
wrongful death is a “new right of action” created by statute);
Putman v. S. Pac. Co., 27 P. 1033, 1033-34 (Or. 1891)
(same). Under these precedents, Oregon Revised Statutes sec-
                FIELDS v. LEGACY HEALTH SYSTEM              7419
tion 30.020 and Oregon Revised Statutes section 12.110(4) do
not violate Article I, section 10.

   Second, the Oregon Court of Appeals has held that even if
a common law claim for wrongful death existed in Oregon in
1857, so did a pre-existing territorial law containing a six-year
statute of limitations and statute of repose that accrued at the
time of the occurrence of the tortious act. Barke v. Maeyens,
31 P.3d 1133, 1138 (Or. App. 2001), rev. denied, 45 P.3d 448
(Or. 2002) (citing Statutes of Oregon 1854, Act for the Limi-
tation of Actions, ch. 1, § 4, p.171). In Barke, the court mea-
sured the statute of repose under both the territorial law and
Oregon Revised Statutes section 12.110(4) from the date of
the allegedly negligent medical treatment by the defendant.
Because the plaintiff’s action was commenced more than six
years later, the court ruled that any action at common law
would already have been barred by the law as it existed when
the framers adopted Article I, section 10. Id. at 1139. Accord-
ingly, there could be no constitutional violation. Id. In this
case, the breach of duty that resulted in Laura Fields’ death
occurred on August 3, 1994, but no wrongful death action was
filed until December 23, 2002, more than six years later. As
in Barke, then, there could be no constitutional violation.

   The Oregon Supreme Court will not exercise its discretion
to consider a certified question unless, among other require-
ments, “there is no controlling precedent in the decisions of
the Supreme Court and the intermediate appellate courts of
this state.” Or. Rev. Stat. § 28.200. We therefore must con-
sider cases of the Oregon Court of Appeals before deciding to
certify a question to the Oregon Supreme Court. W. Helicop-
ter, 811 P.2d at 631. Barke, a decision by the Oregon Court
of Appeals, holds that Oregon’s wrongful death statutes of
limitations and repose, as applied here, do not violate Article
I, section 10, of the Oregon Constitution. In view of that hold-
ing, we decline to certify to the Oregon Supreme Court the
remedy clause question framed by George Fields.
7420            FIELDS v. LEGACY HEALTH SYSTEM
   We also decline to certify the question urged by George
Fields of whether Oregon’s wrongful death statutory scheme
violates the Oregon Constitution’s privileges and immunities
clause. Article I, section 20 of the Oregon Constitution pro-
vides that: “No law shall be passed granting to any citizen or
class of citizens privileges, or immunities, which, upon the
same terms, shall not equally belong to all citizens.” George
Fields argues that Oregon’s wrongful death statute of limita-
tions and statute of repose violate Article I, section 20
because they impermissibly discriminate between classes of
wrongful death claimants whose decedents happen to survive
more than three years after discovery of the injury causing the
death, as in Laura Fields’ case, and claimants whose dece-
dents died within three years of discovering the injury causing
death.
   The Oregon Supreme Court rejected a challenge to a very
similar classification in Sealey, 788 P.2d at 440. The Sealey
plaintiff argued that Oregon’s products liability statute of
repose, which required products liability cases to be brought
within eight years after the date of purchase, violated the state
privileges and immunities clause because it denied persons
injured by products more than eight years after their initial
sale the same legal claims as persons injured by products sold
more recently.
   The Sealey court stated:
     The question is whether plaintiff is a member of a
     class, some of whom have been denied a privilege or
     immunity granted to others in the same class, or
     whether the manufacturers and sellers of products
     have been granted a privilege or immunity not avail-
     able equally to others in the same class. In evaluating
     whether a class exists under Article I, section 20, we
     must first determine whether the class is created by
     the challenged law itself or by virtue of characteris-
     tics apart from the law in question.
                FIELDS v. LEGACY HEALTH SYSTEM               7421
Id. (internal citation, quotation marks and ellipsis omitted;
emphasis added).
   Applying this standard, the Sealey court held that the
classes alleged by the plaintiff were improper because they
were “clearly classes ‘created by the challenged law itself.’ ”
Id. The court further explained that, “[a]ny statute of repose,
by setting a time limit beyond which the legislature declines
to recognize the existence of a legal injury, will divide tortfea-
sors and their victims into classes based upon those time lim-
its. However, such a decision is within the purview of the
legislature.” Id. (emphasis added). See also Van Wormer v.
City of Salem, 788 P.2d 443, 446 (Or. 1990) (rejecting chal-
lenge to a classification which “exist[ed] only because the
statutory scheme of which it [wa]s a part exist[ed]” and which
was “not based on any ad hominem characteristic, such as
race, sex or religious affiliation, of [class] members”).
   The allegedly unconstitutional classification here is simi-
larly based on the time limits the Oregon statutes impose on
wrongful death claimants, rather than on any personal charac-
teristics of wrongful death claimants whose decedents happen
to survive more than three years after discovering the injury
causing their deaths. Thus, there is no open question under
Oregon case law about whether George Fields has identified
an actionable class under the Oregon Constitution’s privileges
and immunities clause. We therefore decline to certify this
issue for the Oregon Supreme Court’s consideration.
                               VII
   We affirm the district courts’ choice of Oregon law, decline
to toll Oregon’s wrongful death statute of limitations, and
conclude that the UCLLA’s “escape clause” does not permit
George Fields to proceed with his action in the Washington
district court. We also hold that the Oregon statutes of limita-
tions and repose violate neither the United States Constitution
nor the Oregon Constitution.
   AFFIRMED.
7422            FIELDS v. LEGACY HEALTH SYSTEM
GOULD, Circuit Judge, concurring:

   I write separately and additionally to express regret that we
have no ability, in this diversity case, to reexamine controlling
Oregon precedent on the state constitutional remedy clause
issue and to allow a remedy to be given to the decedent’s
daughter. The Oregon Supreme Court and its intermediate
appellate courts have consistently held that there was no com-
mon law right to recover for wrongful death. The Oregon
Supreme Court has twice expressed misgivings about its pre-
cedent. Storm v. McClung, 47 P.3d 476, 482 & n.4 (Or. 2002)
(explaining that “[t]his court has previously has been apprised
of the questionable premise underlying the widely held view
that there was no common-law action for wrongful death
[and] acknowledged as much” but declining to consider the
question because it “is beside the point in this case”); Goheen
v. Gen. Motors Corp., 502 P.2d 223, 225-27 (Or. 1972)
(reviewing history of wrongful death actions in Oregon and
stating that “[a]lthough there may be some merit in that view
[that Oregon had a common law right of action for wrongful
death], our own previous decisions are to the contrary, and we
prefer to rest our decision in this case on other grounds”).
Nonetheless, the Oregon Supreme Court has not expressly
overruled its prior precedent, and we are not at liberty to alter
a state’s established case law on a state law issue. It is further
regrettable that we cannot properly tender the remedy clause
issue to the Oregon Supreme Court for its decision, because
the Oregon Supreme Court has been explicit in setting its cer-
tification guidelines, and under those standards this issue may
not now be certified. If change is to come in Oregon’s state
law, bringing Oregon into alignment with the growing num-
ber of other jurisdictions that recognize a common law
wrongful death action, LaFage v. Jani, 766 A.2d 1066, 1079
(N.J. 2001); Haakanson v. Wakefield Seafoods, Inc., 600 P.2d
1087, 1092 & n.11 (Alaska 1979); Wilbon v. D. F. Bast Co.,
382 N.E.2d 784, 785-87 (Ill. 1978); Rohlfing v. Moses
Akiona, Ltd., 369 P.2d 96 (Haw. 1961), overruled on other
grounds by Greene v. Texeira, 505 P.2d 1169 (Haw. 1973);
              FIELDS v. LEGACY HEALTH SYSTEM          7423
Gaudette v. Webb, 284 N.E.2d 222, 229 (Mass. 1972), it must
come by action of the Oregon Supreme Court, and not from
this Court.
