Colorado’s Undiscoverable-Injury Exception Does Not Require Discovery After Three Years

1. Introduction

In Lewis v. United States, the Tenth Circuit addressed whether Colorado’s three-year medical-malpractice statute of repose bars a claim when the patient discovers her physical injury before that three-year period expires. The court held that the statutory exception for an unknown or reasonably undiscoverable physical injury and its cause does not require discovery to occur after the repose period. Courts cannot insert that additional condition into the statute.

Kate Lewis and her husband, Jeffrey Lewis, alleged that negligent examination of a breast lump at a federally funded clinic delayed the diagnosis and treatment of her cancer, worsening her prognosis. They sued the United States under the Federal Tort Claims Act (FTCA). The district court entered summary judgment for the government because the lawsuit was filed more than three years after the allegedly negligent examination.

The appellate court reversed. Its decision concerns the availability of a statutory exception to the repose bar—not whether the clinic was negligent, whether any negligence caused the alleged harm, or whether the Lewises ultimately should recover damages.

2. Background and Procedural History

The medical chronology

• February 2017: Lewis visited Peak Vista Community Health Center in Colorado Springs after feeling a lump in her left breast. A nurse practitioner examined her, reassured her, and advised that further testing was unnecessary. Whether the practitioner identified abnormalities was disputed.
• Approximately one year later: Lewis underwent breast augmentation. Her plastic surgeon identified no lump during the preoperative or postoperative period, and Lewis did not mention the 2017 examination.
• June and July 2019: After Lewis noticed breast deformation, a doctor identified a lump, which the plastic surgeon subsequently confirmed. A July mammogram was negative.
• December 2019: Following complaints that the lump had become painful, the plastic surgeon performed a lumpectomy and informed Lewis that it was cancerous.
• January 2020 onward: Lewis underwent a double mastectomy and learned that the cancer had spread to her lymph nodes. She began oncology treatment the following month and learned approximately one year later that her prognosis was likely terminal.

The litigation

The Lewises submitted an administrative claim to the Department of Health and Human Services in December 2021. After the Department denied it in July 2022, they filed their lawsuit that month.

The government repeatedly invoked Colorado’s three-year statute of repose. The district court initially dismissed the action, reconsidered that ruling because factual questions might prevent application of the statute, and allowed an amended complaint to proceed. After discovery, however, it granted summary judgment to the government.

The district court interpreted the undiscoverable-injury exception as applying only when the injury and its cause remained unknown or reasonably undiscoverable throughout the three-year repose period. Because Lewis discovered her cancer within that period, the court concluded that the exception did not protect her claim.

3. Summary of the Opinion

The Tenth Circuit rejected the district court’s interpretation of Colorado Revised Statutes § 13-80-102.5(3)(c). That provision creates an exception:

“If both the physical injury and its cause are not known or could not have been known by the exercise of reasonable diligence.”

Nothing in that language requires the injury and its cause to remain undiscovered until after the three-year period expires. The statute’s introductory language also expressly states that the limitations in subsection (1), which include the repose period, do not apply when an enumerated exception is satisfied.

On the summary-judgment record, the parties did not dispute that Lewis suffered a physical injury or that there was a period during which she neither knew nor reasonably could have known of the injury and its cause. The court therefore held that subsection (3)(c) applied and that the three-year repose period did not bar the action.

Disposition: The court reversed summary judgment and remanded for further proceedings.

4. Legal Framework and Reasoning

A. The FTCA incorporates state substantive liability rules

The FTCA generally makes the United States liable for its agents’ torts when a private person would be liable under the law of the place where the conduct occurred. Because the alleged malpractice occurred in Colorado, Colorado substantive law supplied the relevant liability rules.

The Lewises conceded that Colorado’s statute of repose was substantive, and the court accepted that concession for this appeal. It did not independently decide the classification question.

Federal law separately governs FTCA filing deadlines. Under 28 U.S.C. § 2401(b), a claimant generally must present an administrative claim within two years after accrual and commence suit within six months after the agency’s final denial. The government conceded compliance with the six-month requirement, and its summary-judgment motion did not challenge compliance with the two-year requirement. Consequently, the appeal did not resolve any contested question about federal accrual or administrative-claim timeliness.

B. Limitations and repose measure time differently

Colorado’s medical-malpractice statute ordinarily contains two deadlines:

• A two-year limitation period: This ordinarily runs from accrual, defined by reference to when the injury and its cause are known or should have been known through reasonable diligence.
• A three-year repose period: This runs from the defendant’s act or omission, regardless of when the claimant discovers the injury.

That distinction was decisive. A discovery-based provision concerns accrual; it does not become a repose provision merely because it contains a time limit. Repose measures time from the defendant’s conduct, whereas an accrual rule measures time by reference to the claimant’s knowledge or discoverability of the relevant facts.

C. The exception contains no three-year discoverability requirement

The district court reasoned that reasonable diligence necessarily implied a period within which the patient should discover the injury. It selected the three-year repose period as that interval.

The Tenth Circuit found no textual basis for this addition. Subsection (3)(c) does not say that the injury and its cause must remain undiscoverable “within three years” or “until the repose period expires.” Its language addresses knowledge and reasonable discoverability without attaching either to a period measured from the negligent act.

The court therefore treated the district court’s construction as adding a substantive restriction that the legislature had not enacted. The fact that discovery occurred before the ordinary repose deadline did not, by itself, defeat the exception.

D. The surrounding statutory structure reinforces the text

Subsection (3) begins by stating that the “limitation of actions provided in subsection (1)” does not apply in the listed circumstances. The appellate court read that umbrella language as displacing both subsection (1)’s two-year limitation period and its three-year repose period when an exception applies.

The neighboring exceptions supported this reading. Subsections (3)(a) and (3)(b), addressing knowing concealment and unauthorized foreign objects, provide two-year periods measured from discovery of the act or omission. These are replacement limitation periods, not replacement repose periods.

The court corrected both parties on this point: neither provision establishes a new period running from the defendant’s last culpable act. Likewise, subsection (3)(c) does not recreate the repose restriction from which it supplies an exception.

E. Potential breadth did not justify rewriting the exception

The government argued that the court’s interpretation could allow the exception to swallow the general repose rule. The court acknowledged the concern. Subsection (3)(c) closely resembles Colorado’s ordinary discovery-based accrual language, although it expressly refers to “physical injury.”

Nevertheless, the court declined to resolve two broader questions unnecessary to this FTCA appeal:

1. Whether subsection (3)(c)’s accrual rule is narrower than the general accrual rule in § 13-80-108(1).
2. What state-law limitation period applies under subsection (3)(c), which does not expressly specify its length.

Because federal law supplied the applicable limitation period here, the court needed to decide only whether subsection (3)(c) preserved or reinstated a repose bar. It held that the statutory language did neither.

F. Application to Lewis’s claim

The court did not need to choose between cancer itself and its metastasis as the relevant injury: either was a physical injury. It also found no dispute that some period elapsed during which Lewis neither knew nor reasonably could have known of the injury and its cause. Her later cancer diagnosis and the negative July 2019 mammogram supported that conclusion on the record before the court.

The decision does not establish that a negative mammogram always proves reasonable diligence, or that every delayed-diagnosis claim satisfies the exception. Its application rested on the undisputed circumstances presented at summary judgment.

5. Precedents Cited and Their Influence

A. Appellate review and the factual record

Chase Mfg., Inc. v. Johns Manville Corp., 84 F.4th 1157 (10th Cir. 2023)

This decision supplied the summary-judgment framework: review is de novo, and judgment is appropriate only when no genuine dispute of material fact exists and the movant is entitled to judgment as a matter of law. It also supported viewing the record favorably to the Lewises. Its influence was procedural rather than interpretive: the appellate court independently reconsidered the district court’s legal reading.

Manning v. City of Tulsa, 170 F.4th 1287 (10th Cir. 2026)

The court cited this case for drawing the factual account from the parties’ summary-judgment submissions while identifying disputed matters. That approach explains why the opinion acknowledged disagreement about the nurse practitioner’s examination without resolving the underlying malpractice allegations.

B. FTCA liability and substantive state law

Martin v. United States, 605 U.S. 395 (2025)

This Supreme Court decision supplied the central FTCA proposition: the federal liability rule incorporates state law. It explained why Colorado’s substantive medical-malpractice rules mattered even though the defendant was the United States and the action proceeded under federal law.

Gonzalez v. United States, 80 F.4th 183 (2d Cir. 2023)

The opinion cited this decision as additional support for applying state substantive law while federal law governs procedural matters in FTCA litigation. Its role was corroborative; it did not determine the meaning of Colorado’s exception.

Bennett v. United States, 44 F.4th 929 (9th Cir. 2022)

This case provided a procedural analogue for accepting a plaintiff’s concession that a state repose statute is substantive. The Tenth Circuit similarly accepted the Lewises’ concession without turning that accepted premise into an independent holding about Colorado law.

Augutis v. United States, 732 F.3d 749 (7th Cir. 2013)

The court cited this decision’s holding that Illinois’s statute of repose is substantive. It illustrated the broader treatment of repose as a liability restriction, but it did not answer the distinct question whether Colorado’s statutory exception applied.

Anderson v. United States, 669 F.3d 161 (4th Cir. 2011)

This decision described repose statutes as substantive limitations on liability and certified a question concerning whether Maryland’s statute was one of limitation or repose. Its significance lies in distinguishing the legal effect of repose from ordinary filing deadlines while recognizing that classification depends on the particular state statute.

C. Statutory interpretation

Finstuen v. Crutcher, 496 F.3d 1139 (10th Cir. 2007)

This case established the methodological starting point: federal courts interpreting state statutes apply the state’s rules of statutory construction. Accordingly, the panel used Colorado interpretive principles rather than an independent federal policy concerning malpractice claims.

Sentinel Colo. v. Rodriguez, 577 P.3d 48 (Colo. 2025)

This decision supplied Colorado’s text-and-context approach: give statutory language its plain and ordinary meaning, read provisions consistently with the statutory design, and avoid illogical or absurd results. It also supported ending the interpretive inquiry once the text was clear, rather than pursuing the parties’ competing accounts of legislative intent.

Smokebrush Found. v. City of Colorado Springs, 410 P.3d 1236 (Colo. 2018)

This was especially important to the result. Its instruction that courts may not add or subtract statutory words directly undermined the district court’s insertion of a requirement that nondiscoverability continue throughout the three-year repose period.

Elder v. Williams, 477 P.3d 694 (Colo. 2020)

This decision appeared through the court’s quotation of Sentinel Colo. v. Rodriguez. It reinforced the principle that clear statutory language makes further interpretive inquiries unnecessary. Its influence was supporting rather than independently dispositive.

D. Repose and the medical-malpractice exceptions

CTS Corp. v. Waldburger, 573 U.S. 1 (2014)

This Supreme Court decision supplied the conceptual distinction between limitation and repose. Repose runs from the defendant’s culpable act or omission and reflects a legislative judgment about eventual freedom from liability. That distinction enabled the panel to explain why discovery-based periods in neighboring exceptions were not new repose periods and why subsection (3)(c) contained no repose requirement.

Jones v. United States, No. 05-cv-00369, 2006 WL 8454880 (D. Colo. July 24, 2006) (unpublished)

The district court relied on this decision for the proposition that the injury and its cause must remain unknown or undiscoverable within the three-year period. The Tenth Circuit rejected that construction because it lacked support in the statutory text. The reversal thus rejected the interpretive premise borrowed from this district-court authority.

Austin v. Litvak, 682 P.2d 41 (Colo. 1984)

Addressing an earlier statutory version, the Colorado Supreme Court described the relevant provisions as exceptions to the three-year statute of repose. The panel used that characterization to reinforce its structural analysis. It did not treat this earlier decision as directly resolving the precise interpretation of subsection (3)(c) presented here.

6. Potential Impact and Limits

Delayed discovery is not confined to discovery after repose expires

The opinion’s principal practical significance is its rejection of an added timing threshold. Under its reasoning, a claimant is not excluded from subsection (3)(c) merely because the injury becomes discoverable before the third anniversary of the alleged malpractice. That interpretation may be particularly important in delayed-diagnosis litigation.

The factual inquiry remains important

Future disputes may focus on whether the injury is physical, what the claimant knew about the injury and its cause, and what reasonable diligence would have revealed. The decision does not dispense with those requirements. Nor does it establish the exception’s boundaries for every medical-malpractice claim.

Other deadlines and liability requirements remain

Removing the repose bar does not establish timely filing under every applicable limitation rule. It also does not prove breach of the standard of care, causation, or damages. Those issues remain distinct from the statutory ground resolved on appeal.

Several broader issues remain open

The court expressly did not decide the Lewises’ FTCA-preemption argument, their constitutional challenge to the district court’s interpretation, or their alternative argument that factual disputes prevented summary judgment under the repose statute. It also left unresolved the state-law limitation period applicable under subsection (3)(c).

Finally, because the disposition is nonprecedential, its reasoning is persuasive rather than generally binding. Its analysis may influence later courts, but it should not be described as a binding circuit-wide or Colorado Supreme Court resolution of the statute.

7. Complex Concepts Simplified

Statute of limitations

A deadline generally connected to when a claim accrues—for example, when a person knows or reasonably should know of an injury and its cause.

Statute of repose

An outside deadline measured from the defendant’s conduct. Unless an exception applies, it can bar a claim before the injured person discovers it.

Accrual

The event that starts the limitations clock. Identifying accrual is different from identifying the date of the allegedly negligent treatment.

Reasonable diligence

The reasonable steps a person should take to investigate relevant facts. It concerns what reasonably could have been discovered, not just what the person actually knew.

Summary judgment and de novo review

Summary judgment resolves a case without trial when no material factual dispute requires one. De novo review means the appellate court independently evaluates the ruling without deferring to the district court’s legal conclusions.

Statutory exception versus tolling

The court applied an express legislative exception making the repose bar inapplicable. It did not merely pause the three-year clock through an equitable extension.

Nonprecedential decision

A decision that generally does not bind courts in unrelated cases, although its reasoning may persuade them and the judgment may bind the parties through specified preclusion doctrines.

8. Conclusion

Lewis v. United States rests on a straightforward interpretive principle: courts may not add a timing restriction to an express statutory exception. Colorado’s undiscoverable-physical-injury exception does not require discovery after the three-year repose period expires.

Because the undisputed record satisfied that exception, the Tenth Circuit restored the Lewises’ opportunity to pursue their claims. Its persuasive significance lies in separating discovery-based accrual from conduct-based repose while leaving negligence, causation, other timeliness questions, and the exception’s broader boundaries for later proceedings.