FILED
                                                                     United States Court of Appeals
                      UNITED STATES COURT OF APPEALS                         Tenth Circuit

                             FOR THE TENTH CIRCUIT                        November 29, 2019
                         _________________________________
                                                                          Elisabeth A. Shumaker
                                                                              Clerk of Court
 DEREK THOMPSON, individually and as
 personal representative of the estate of
 Cynthia Thompson,

       Plaintiff - Appellant,
                                                             No. 18-1422
 v.                                             (D.C. No. 1:16-CV-01202-PAB-KLM)
                                                              (D. Colo.)
 STATE FARM MUTUAL
 AUTOMOBILE INSURANCE
 COMPANY,

       Defendant - Appellee.
                      _________________________________

                             ORDER AND JUDGMENT*
                         _________________________________

Before BACHARACH, McKAY, and CARSON, Circuit Judges.
                 _________________________________

      This case involves a dispute over underinsured motorist (“UIM”) coverage.

Cynthia Thompson was injured in a car accident. Six months later, she died after

overdosing on prescription drugs. Her son Derek Thompson (“Plaintiff”) sued Ms.

Thompson’s insurer, State Farm Mutual Automobile Insurance Company (“State

Farm”), after it refused to pay UIM benefits. State Farm moved for summary

judgment, which the district court granted. Plaintiff now appeals.



      *
         This order and judgment is not binding precedent, except under the doctrines
of law of the case, res judicata, and collateral estoppel. It may be cited, however, for
its persuasive value consistent with Fed. R. App. P. 32.1 and 10th Cir. R. 32.1.
      We exercise jurisdiction under 28 U.S.C. § 1291 and consider whether

Plaintiff demonstrated the existence of a fact issue as to whether the car accident

proximately caused Ms. Thompson’s overdose and resulting death. Because Plaintiff

met his burden, we reverse and remand for further proceedings.

                                           I.

      In August 2013, an underinsured motorist failed to yield to the vehicle in

which Ms. Thompson was a passenger. The resulting collision broke Ms.

Thompson’s neck.1 For the next several months, Ms. Thompson’s doctors prescribed

oxycodone and diazepam to alleviate her pain.

      Six months later, Ms. Thompson died at home. The physician who performed

the autopsy, Dr. Robert Kurtzman, concluded she died after overdosing on

prescription drugs. Dr. Kurtzman detected no oxycodone in her blood. Instead, he

discovered a fentanyl patch on her back, and both fentanyl and diazepam in her

blood. Dr. Kurtzman opined the combination of fentanyl and diazepam caused an

accidental overdose that resulted in her death. As it turns out, Ms. Thompson had a

history of neck pain. And years before this accident, Ms. Thompson’s doctors

prescribed her fentanyl to treat and alleviate that neck pain. In fact, her medical

records reveal she last received a prescription for fentanyl in 2010. Plaintiff

explained that Ms. Thompson used a leftover fentanyl prescription as a substitute for

the oxycodone because the oxycodone caused extreme nausea. But because she was


      1
        Specifically, Ms. Thompson suffered a hangman’s fracture, which involves a
fracture of the second vertebra toward the top of the neck, close to the skull.
                                           2
no longer a regular fentanyl user, she lost her tolerance to it, and the combination of

fentanyl and diazepam proved deadly. It thus appears that Ms. Thompson died from

an attempt at self-medication.

      After Ms. Thompson passed away, Plaintiff sent a demand letter to State Farm

claiming his mother’s UIM benefits. State Farm, however, refused to pay benefits

because the car accident did not cause her overdose and resulting death. Plaintiff

sued State Farm and sought a declaration of his entitlement to UIM benefits under the

State Farm policies. In a summary judgment motion before the district court, State

Farm argued that Ms. Thompson’s self-medication, not the car crash, proximately

caused her death. In other words, State Farm argued that her self-medication

intervened to break the chain of causation. State Farm claimed it could not foresee

that a car accident might cause Ms. Thompson to overdose on a medication that

doctors last prescribed in 2010—some three years before the accident. Plaintiff

countered that it is foreseeable that an injured person like Ms. Thompson would use a

leftover medication, especially because Ms. Thompson had previously used that same

medication to treat a similar type of pain. The district court agreed with State Farm,

concluding as a matter of law that Ms. Thompson’s fentanyl use constituted an

intervening act that severed the chain of causation between the accident and her

death. The district court therefore granted summary judgment in favor of State Farm.

We exercise jurisdiction under 28 U.S.C. § 1291, and our review is de novo.

Carpenter v. Boeing Co., 

, 1192 (10th Cir. 2006) (“Our standard of



                                           3
review on summary judgment is de novo; we apply the same legal standard to be used

by the district court.”).

                                            II.

                                            A.

       Plaintiff originally filed suit in Colorado state court. But State Farm removed

the case to federal district court on the basis of diversity jurisdiction. A federal court

sitting in diversity applies state substantive law. Racher v. Westlake Nursing Home

Ltd. P’ship, 

, 1162 (10th Cir. 2017). The parties agree that Colorado

tort law governs the causation issue in this case.

       Before the district court, Plaintiff sought a declaration that he is entitled to

UIM benefits under the terms of State Farm’s policies.2 Colorado law requires

insurers to “pay to the insured, up to the limit of the policy, whatever losses the

insured proves he or she is ‘legally entitled to recover’ from the uninsured motorist.”

Briggs v. Am. Family Mut. Ins. Co., 

, 861 (Colo. App. 1992) (quoting

Colo. Rev. Stat. § 10-4-609(a)(1), (4)). Thus, to recover, the insured must prove the

“underinsured motorist was negligent and the extent of the damages.” 

(1) the existence of a legal duty; (2) breach of that duty;

(3) causation; and (4) damages. HealthONE v. Rodriguez ex rel. Rodriguez, 

, 888 (Colo. 2002) (en banc). The causation element comprises both actual

causation and proximate causation. See Moore v. W. Forge Corp., 

, 436


       2
        State Farm does not dispute that Plaintiff is an “insured” for purposes of
recovering UIM benefits.
                                             4
(Colo. App. 2007). Actual causation asks whether the defendant’s negligence was

the but-for cause of the plaintiff’s harm—that is, “whether, but for the alleged

negligence, the harm would not have occurred.” N. Colo. Med. Ctr., Inc. v. Comm.

on Anticompetitive Conduct, 

, 908 (Colo. 1996) (en banc) (quoting

Smith v. State Comp. Ins. Fund, 

, 464 (Colo. App. 1987)).

      Proximate causation, on the other hand, addresses foreseeability. Westin

Operator, LLC v. Groh, 

, 614 n.5 (Colo. 2015). Proximate causation

evaluates whether the defendant’s negligence will foreseeably result in injuries to

others. Build It & They Will Drink, Inc. v. Strauch, 

, 306 (Colo. 2011)

(en banc). The foreseeability analysis does not require a defendant “to foresee the

exact nature and extent” of the injuries. 

50 P.3d at 889).

Nor does it require the defendant to foresee the “precise manner in which” the

tortious conduct caused the injuries. 

. Instead, the

defendant must only foresee that “some injury will likely result in some manner”

because of his negligent acts. 

      Even so, proximate causation is not so broad as to result in unlimited liability.

On the contrary, proximate causation limits a negligent actor’s liability when an

unforeseeable cause intervenes to bring about an injury. See 

.

In other words, an “intervening cause” relieves a defendant of liability when the

defendant could not have reasonably foreseen it. Redden v. SCI Colo. Funeral

Servs., Inc., 

, 81 (Colo. 2001) (en banc). Proximate causation is generally

resolved by the trier of fact. Hilzer v. MacDonald, 

, 929 (Colo. 1969)

                                           5
(en banc). “[O]nly in the clearest of cases, where the facts are undisputed and

reasonable minds could draw but one inference” may the court decide proximate

causation as a matter of law. 

district court concluded that Plaintiff failed to present sufficient evidence

of proximate causation to survive summary judgment.3 More specifically, the district

court held Ms. Thompson’s use of an unprescribed narcotic to be unforeseeable as a

matter of law. While no Colorado court has directly addressed foreseeability in this

context, Colorado appellate decisions nonetheless emphasize that proximate

causation is generally a fact question for the jury. See, e.g., Build It and They Will

Drink, 

. For that reason, a court may decide proximate causation

as a matter of law only when reasonable minds could reach but one conclusion from

the evidence. Roberts v. Fisher, 

, 872 (Colo. 1969) (en banc).



      3
        For the first time on appeal, State Farm now appears to challenge actual
causation. State Farm alleges that no evidence shows that Ms. Thompson used the
fentanyl patch to treat pain resulting from the car accident.
       We decline to consider State Farm’s arguments pertaining to actual causation.
In its motion for summary judgment, State Farm only made arguments regarding
proximate causation and foreseeability. And the district court assumed “that Ms.
Thompson used the fentanyl to alleviate pain resulting from injuries sustained in the
car accident.” Indeed, the first time State Farm even arguably raised the issue of
actual causation was in its summary judgment surreply brief, to which Plaintiff had
no opportunity to respond. Beaird v. Seagate Tech., Inc., 

, 1164 (10th
Cir. 1998) (requiring that the nonmoving party be given notice and a reasonable
opportunity to respond). “Generally, we do not consider issues not presented to,
considered and decided by the trial court.” Utah Envtl. Cong. v. Russell, 

, 828 (10th Cir. 2008) (internal citations and quotation marks omitted). We thus
decline to consider the issue of actual causation.
                                           6
      As we see it, reasonable minds could disagree as to whether Ms. Thompson’s

overdose on pain medication was foreseeable. Plaintiff’s expert opined that “Ms.

Thompson’s manner of death is consistent with that of an accident via what appears a

self-directed attempt to control her pain to prolonged healing of traumatic cervical

spine injury.”4 Plaintiff also presented evidence that Ms. Thompson had a prior

prescription for fentanyl and that she used fentanyl patches to treat neck pain for

many years before the car accident. Plaintiff explained that Ms. Thompson replaced

the oxycodone with a leftover fentanyl patch because the oxycodone caused her to

experience extreme nausea. The district court accepted Plaintiff’s evidence but

concluded that Ms. Thompson’s use of a dangerous narcotic was unforeseeable as a

matter of law. In reaching this conclusion, the district court failed to adequately

consider the context of the situation and draw all inferences in Plaintiff’s favor. As

the record demonstrates, Ms. Thompson successfully used fentanyl patches in the

past to alleviate her neck pain. Then, after suffering a broken neck in the car crash,

her neck pain returned. Plaintiff presented evidence that Ms. Thompson stopped

using the prescribed oxycodone because it made her sick and instead used a leftover

fentanyl patch—a medication she used (with a prescription) in the past to treat a



      4
         State Farm states in one perfunctory sentence that Plaintiff’s expert relied on
inadmissible hearsay. State Farm, however, provides no substantive explanation and
cites no legal authority supporting its position. We therefore deem that argument
waived. Seifert v. Unified Gov’t of Wyandotte Cty/Kan. City, 

, 1156
(10th Cir. 2015) (“[I]ssues adverted to in a perfunctory manner, unaccompanied by
some effort at developed argumentation, are deemed waived.” (alteration in original)
(quoting Murrell v. Shalala, 

, 1389 n.2 (10th Cir. 1994))).
                                           7
similar, if not identical, type of pain. A reasonable jury could conclude that based on

her medical history and prior use of fentanyl patches, it was reasonably foreseeable

that she would use a leftover patch to treat her resurfaced neck pain after the

accident. The district court’s conclusion creates a bright-line rule that automatically

cuts off causation whenever a person overdoses on non-prescribed or leftover

medication. Under Colorado law, however, the fact-intensive nature of proximate

causation and foreseeability cautions against such a bright-line rule.

      Indeed, Colorado courts have held that third-party negligent treatment,5

intentional torts, suicide, and criminal acts may be foreseeable and are more

appropriate for a jury to decide. 

n.2 (recognizing “that

Colorado case law does not absolve tortfeasors of liability when the plaintiff’s

injuries result from medical treatment reasonably sought and directly related to the

actions of the original tortfeasor”); 

–37 (recognizing that

when a defendant’s negligence causes cognitive or psychological injury to a person, a

jury may decide whether the person’s subsequent suicide was foreseeable to the



      5
        State Farm argues that Ms. Thompson was grossly negligent because she was
a nurse, and a nurse’s decision to take a dangerous narcotic cannot be viewed as
simple negligence. And because Ms. Thompson’s conduct rises to the level of gross
negligence, that conduct was unforeseeable as a matter of law. In civil cases,
however, the factfinder “must weigh the conduct of the parties, be it slightly, grossly,
recklessly or willfully negligent, and make the appropriate percentage allocation of
fault.” White v. Hansen, 

, 1234 (Colo. 1992) (en banc). Our task is
simply to determine whether Ms. Thompson’s conduct was reasonably foreseeable.
Then, the jury can separately evaluate whether Ms. Thompson’s conduct was also
grossly negligent and assign her an appropriate percentage of fault based on that
conduct.
                                           8
defendant); Eckberg v. Greene, 

, 377 (Colo. 1978) (en banc) (reversing

the lower’s court finding that proximate causation did not exist even though the

plaintiffs were trespassers who were injured by the acts of other trespassers).

Colorado courts thus strongly favor having juries resolve proximate causation

questions. And while not binding in this case, the weight of authority from other

jurisdictions also suggests that a jury should resolve whether proximate causation

exists when a decedent overdoses on medication, illicit drugs, or alcohol.6 We

likewise hold that a jury should decide proximate causation here.

      Because Plaintiff presents evidence that Ms. Thompson used the fentanyl patch

to alleviate pain resulting from her accident-related injuries, we conclude that a

reasonable jury could find that Ms. Thompson’s accident-related pain proximately

caused her overdose.7




      6
         See e.g., Fennell v. Md. Cas. Co., 

, 355 (Tenn. 1961);
Clemons v. Miele, No. UWYCV116010477, 

, at *6–7 (Conn.
Super. Ct. July 2, 2013); Joseph E. Seagram & Sons, Inc. v. Willis, 

,
91–92 (Ind. Ct. App. 1980); Paul v. State Farm Mut. Auto. Ins. Co., No. 14-1382,

, at *28 (W.D. Pa. Sept. 28, 2016); Leja v. Schmidt Mfg., Inc., No.
01-5042 (DRD), 

, at *7 (D.N.J. July 1, 2010); Wetstein v. W.
Terrace Constr. Co., No. 95 CIV. 5476 (CSH), 

, at *3–4 (S.D.N.Y.
July 16, 1999). But see Brown v. N.Y. State Training Sch. for Girls, 

,
784 (N.Y. 1941); Keusch v. Farm Bureau Ins. Co., No. 297642, 

,
at *6 (Mich. Ct. App. Aug. 30, 2011).
       7
         Because the district court ruled on proximate causation as a matter of law, it
did not reach alternative arguments for summary judgment. We decline to consider
any alternative arguments and remand all of Plaintiff’s claims to the district court.
Sylvia v. Wisler, 

, 1326 (10th Cir. 2017) (concluding that the “most
prudent and fair course is to allow the district court to address this [alternative] claim
in the first instance on remand”).
                                            9
                                            III.

      For the foregoing reasons, we REVERSE the district court’s grant of summary

judgment and REMAND for further proceedings consistent with this opinion.


                                        Entered for the Court


                                        Joel M. Carson III
                                        Circuit Judge




                                       10