PUBLISHED

UNITED STATES COURT OF APPEALS

FOR THE FOURTH CIRCUIT

No. 19-1609

GARY ADAMS,

 Plaintiff – Appellant,

v.

AMERICAN OPTICAL CORPORATION; MINE SAFETY APPLIANCES 

COMPANY,

 Defendants – Appellees,

and

COAST HOLDINGS, INCORPORATED; 3M COMPANY, as successor by 

merger to Minnesota Mining and Manufacturing Company and/or its 

predecessors/successors in interest,

 Defendants.

Appeal from the United States District Court for the Western District of Virginia, at Big 

Stone Gap. James P. Jones, District Judge. (2:16-cv-00027-JPJ-JMS)

Argued: September 8, 2020 Decided: November 6, 2020

Before KING and FLOYD, Circuit Judges, and Thomas S. KLEEH, United States District 

Judge for the Northern District of West Virginia, sitting by designation.

Affirmed by published opinion. Judge Floyd wrote the opinion, in which Judge King and 

Judge Kleeh joined.
2

ARGUED: Michael Blair Martin, MARTIN WALTON LAW FIRM, Houston, Texas, for 

Appellant. Milton Trent Spurlock, DINSMORE & SHOHL LLP, Louisville, Kentucky; 

Carol Dan Browning, STITES & HARBISON, PLLC, Louisville, Kentucky, for Appellees. 

ON BRIEF: Bethany A. Breetz, STITES & HARBISON, PLLC, Louisville, Kentucky; 

Chad M. Eggspuehler, TUCKER ELIS LLP, Cleveland, Ohio, for Appellees.
3

FLOYD, Circuit Judge:

Plaintiff-Appellant Gary Adams appeals from a district court order entering 

summary judgment in favor of Defendants-Appellees American Optical Corporation (AO)

and Mine Safety Appliances Company (MSA) (collectively, “Defendants”).1 Defendants 

moved for summary judgment on the sole basis that Virginia’s two-year statute of 

limitations barred Adams’s state-law personal injury claims. Thus, the only question 

before this Court is whether Adams filed his personal injury suit outside the two-year 

limitations window.

I.

A.

Between 1981 and 2014, Adams worked as a coal miner, which exposed him to

harmful coal dust. During that period, Adams was given and wore respirators allegedly

produced by Defendants to protect himself from inhaling excessive amounts of that dust.

Adams contends that these respirators failed to protect him from lung disease that he 

developed by inhaling coal dust, while Defendants argue his illness developed outside the 

statute of limitations. We begin with a review of Adams’s medical history.

1 Adams voluntarily dismissed his claims against Defendant 3M Company. See 

Order of Voluntary Dismissal of 3M Co., Adams v. Am. Optical Corp., No. 2:16-cv-00027 

(W.D. Va. Apr. 22, 2019), ECF No. 81. Claims against Defendant Coast Holdings 

Incorporated were later dismissed by oral order of the court. Oral Order, Adams v. Am. 

Optical Corp., No. 2:16-cv-00027 (W.D. Va. May 17, 2019), ECF No. 110.
4

To promote the early detection of mining-related illnesses, the National Institute for 

Occupational Safety and Health (NIOSH) administers a program that gives free x-rays to

coal miners. These x-rays are reviewed by NIOSH-certified B-readers who look for any 

abnormalities in a miner’s lungs.

2 However, NIOSH does not use these x-rays to formally 

diagnose an individual with a specific occupational illness. X-ray evidence of coal dust 

exposure resembles multiple non-occupational diseases, so any abnormalities must be 

“clinically correlated” through other forms of testing. J.A. 889–93.

In 2000, Adams received a NIOSH x-ray and was later informed by the Mine Safety 

and Health Administration (MSHA) that the B-reader found evidence of Category 1 coal 

workers’ pneumoconiosis (CWP). CWP, known colloquially as “black lung,” is a latent 

occupational disease marked by fibrosis, or scarring, of the lungs and caused by inhalation 

of coal dust. It can take years of coal dust exposure for CWP to develop, and it progresses 

slowly once it occurs. The disease progresses through three stages of simple CWP—

beginning with Category 1 and advancing to Category 3—followed by three stages of 

complicated CWP—beginning with Category A and ultimately becoming Category C. 

Adams received another NIOSH x-ray in 2006 and was sent a letter indicating the

B-reader found “DEFINITE EVIDENCE of CATEGORY 1 PNEUMOCONIOSIS.” J.A. 

56. MSHA letters that Adams received in 2000 and 2006 advised him to contact a doctor

2 B-readers are physicians who have passed a NIOSH-approved test demonstrating 

their ability to “interpret[] chest radiographs for pneumoconiosis and other diseases.” 42 

C.F.R. § 37.52(b)(2).
5

and informed him that he was eligible to transfer to a less dusty area of the mine. At that 

time, Adams felt “wide open healthy and wasn’t having any problems,” so he declined to 

transfer positions. J.A. 558. But in 2007, he decided to visit Dr. Mahmood Alam for 

further evaluation.

3 Dr. Alam performed a CT scan and pulmonary function testing, which 

led him to conclude that NIOSH’s findings could not be clinically correlated. Dr. Alam

did not diagnose Adams with CWP, because he believed at the time that Adams’s abnormal 

x-ray results were caused by calcified granulomas on his lungs.

In 2009, Adams was again screened by NIOSH and received another letter 

informing him that his x-ray revealed “DEFINITE EVIDENCE OF CATEGORY 1 

PNEUMOCONIOSIS.” J.A. 67–68. He visited Dr. Alam for a second time and received

another CT scan and round of pulmonary function testing. J.A. 1220–21. Based on those 

results, Dr. Alam continued to believe Adams had calcified granulomas, rather than CWP. 

J.A. 960. 

Between 2010 and 2011, various doctors treated Adams for shortness of breath. In 

2010, Adams’s primary care physician, Dr. April Hall, placed him on an albuterol inhaler 

to help with symptoms of “obstructive lung function.” J.A. 1074.4 In 2011, Adams 

continued to experience shortness of breath along with chest pain, so Dr. Hall referred him 

to a cardiologist, Dr. Jose Velazquez. Dr. Velazquez did not find any coronary artery

3 As discussed below, Dr. Alam subsequently became an expert witness for Adams 

in this case.

4 Defendants’ expert, Dr. James Lockey, believes that Adams may have also 

suffered from allergies and asthma during this time period.
6

diseases and suggested his difficulty breathing might be caused by an underlying lung 

disease. However, medical records from this period also suggest Adams had hypertension, 

which could have contributed to his symptoms. Adams was also referred for a sleep study

in 2011, after which he was diagnosed with severe obstructive sleep apnea. Pulmonary

function testing ordered in 2011 revealed “no airflow obstruction.” J.A. 1332.

Adams received a third x-ray from a non-NIOSH provider on October 25, 2012.

The reviewing physician reported that the “[i]nterstitial process in the lungs [was] slightly 

more impressive than on January 14, 2007[,] consistent with coalworkers pneumoconiosis 

silicosis. Findings appear worse than on previous study.” J.A. 1249. A subsequent x-ray 

performed on August 13, 2013 showed that this “interstitial process in the lungs [was] 

worse than October 25, 2012.” J.A. 1250. Pulmonary function tests in 2013 also indicated 

a “[m]oderate restriction” of Adams’s lung function. J.A. 999–1000.

Up to this point, Adams’s medical records consistently listed CWP as one 

“differential diagnosis” explaining his pulmonary symptoms.5 However, Adams was not 

formally diagnosed with CWP between 2000 and 2013. During this time, medical 

professionals also considered whether his symptoms could be caused by allergies, asthma, 

chronic bronchitis, granulomas, hypertension, or sleep apnea.

5 A differential diagnosis is a collection of illnesses that a doctor believes could

plausibly be causing a patient’s symptoms. As Dr. Alam testified at his deposition, CWP 

will always be part of the differential diagnosis for someone with Adams’s occupational 

history.
7

On October 2, 2014, Adams was diagnosed for the first time with Category B 

complicated CWP—the fifth stage of the disease—after a chest x-ray revealed significant 

“opacities” and “distortion” in his lungs. J.A. 1421–23. By the time Adams was officially 

diagnosed with CWP, he struggled to walk uphill, coughed regularly, and experienced 

chest pain and wheezing with exertion.

Today, Adams is unable to play with his grandchildren, walk the seventy-five feet 

across his property, or shower without breathing problems. Dr. Alam testified that he is a 

potential candidate for a lung transplant.

B.

Adams filed suit in Virginia state court on September 29, 2016, three days shy of 

the two-year anniversary of his diagnosis. His complaint alleged that Defendants’

respirators were defectively and negligently manufactured, breached implied warranties,

and violated federal regulatory requirements. Adams requested compensatory damages 

greater than $75,000 and punitive damages greater than $20 million. Defendants 3M (since 

dismissed) and AO removed the case to the Western District of Virginia on the basis of the 

court’s diversity jurisdiction.

Following discovery, Defendants moved for summary judgment, arguing that 

Adams filed this suit outside the limitations period. At the summary judgment hearing on

May 17, 2019, the district court stated its understanding that Virginia’s two-year statute of 

limitations for personal injury claims runs from the date an injury is received, rather than 

the date it is discovered. Because Adams filed suit on September 29, 2016, he would need 
8

to have not only discovered, but also contracted CWP after September 29, 2014, to avoid 

being time-barred. 

At the summary judgment hearing, Adams conceded that he was diagnosed with 

complicated CWP on October 2, 2014, and that it would not be possible for him to have 

first developed CWP just three days earlier, on September 29, 2014. After the district court 

questioned how this suit could be timely, Adams urged the court to treat his October 2, 

2014 diagnosis as the date on which the limitations period began to run, because that was 

the first time a medical professional “pinpointed” the existence of the disease. J.A. 1644–

45.

In a written order, the district court granted Defendants’ motions for summary 

judgment. The court found that undisputed facts in the record proved CWP is a slowdeveloping disease that could not progress from simple to complicated in the three days

between September 29, 2014 and October 2, 2014. Additionally, medical evidence 

established that Adams developed CWP prior to 2014.6 The court therefore concluded that 

there was no genuine dispute that Adams first suffered CWP outside the limitations period.

6 Adams and Defendants directed the district court to a number of Adams’s medical 

records. They also provided the district court with the depositions of Adams and two expert 

witnesses—Dr. Lockey for Defendants and Dr. Alam for Adams. Dr. Alam and Dr. Lockey 

reviewed Adams’s medical records and concluded that Adams developed CWP well before 

2014. Dr. Alam also provided unrebutted testimony that CWP is a “slow, progressive 

disease.” J.A. 989.
9

II.

A.

This Court reviews the district court’s order granting summary judgment de novo. 

Dash v. Mayweather, 731 F.3d 303, 310 (4th Cir. 2013). Summary judgment is appropriate 

when “there is no genuine dispute as to any material fact and the movant is entitled to 

judgment as a matter of law.” Fed. R. Civ. P. 56(a). To determine whether there is a 

genuine dispute of material fact, a court must “construe the evidence, and all reasonable 

inferences that may be drawn from such evidence, in the light most favorable to the 

nonmoving party.” Dash, 731 F.3d at 311.

Only those facts that could determine the outcome of a case are considered material, 

see Erwin v. United States, 591 F.3d 313, 320 (4th Cir. 2010), and only genuine disputes 

about those facts can defeat summary judgment, Anderson v. Liberty Lobby, Inc., 477 U.S. 

242, 248 (1986). A genuine dispute requires evidence that could allow a reasonable jury 

to find in favor of the nonmoving party. Id. “The mere existence of a scintilla of evidence” 

does not create a genuine dispute of material fact. Id. at 252. The record must instead

permit the conclusion that “reasonable minds could differ” on the issue. Bouchalt v. Balt. 

Ravens Football Club, Inc., 346 F.3d 514, 522 (4th Cir. 2003) (quoting Anderson, 477 U.S. 

at 250).

B.

Because this case was originally brought in Virginia state court and removed to 

federal court on the basis of diversity jurisdiction, “we interpret and apply the substantive 
10

law” of Virginia. Castillo v. Emergency Med. Assocs., P.A., 372 F.3d 643, 646 (4th Cir. 

2004) (citing Erie R.R. v. Tompkins, 304 U.S. 64, 78 (1938)). The substantive law of 

Virginia includes both statutes and the decisions of the Commonwealth’s highest court 

interpreting those statutes. See Johnson v. Hugo’s Skateway, 974 F.2d 1408, 1416–17 (4th 

Cir. 1992) (en banc). This Court treats Virginia’s statute of limitations as substantive when 

reviewing diversity cases. See Joyce v. A.C. & S., Inc., 785 F.2d 1200, 1203 (4th Cir. 

1986).

Two Virginia statutes guide our resolution of this appeal. The first—Va. Code Ann. 

§ 8.01-243(A)—governs the statute of limitations for personal injury causes of action. 

Under section 8.01-243(A), “[u]nless otherwise provided in this section or by other statute, 

every action for personal injuries, whatever the theory of recovery, . . . shall be brought 

within two years after the cause of action accrues.” Va. Code Ann. § 8.01-243(A). The 

second statute—Va. Code Ann. § 8.01-230—governs the accrual of rights of action. Under 

that provision: 

In every action for which a limitation period is prescribed, the right of action 

shall be deemed to accrue and the prescribed limitation period shall begin to 

run from the date the injury is sustained in the case of injury to the 

person . . . and not when the resulting damage is discovered, except where 

the relief sought is solely equitable or where otherwise provided . . . .

Va. Code Ann. § 8.01-230 (emphasis added). 

We start our analysis by examining the distinction between a “cause of action” and 

a “right of action” under Virginia law. See First Va. Bank-Colonial v. Baker, 301 S.E.2d 

8, 13 (Va. 1983) (“This is a distinction with a difference.”). “[A] cause of action is a set of 

operative facts which, under the substantive law, may give rise to a right of action.” Roller 
11

v. Basic Constr. Co., 384 S.E.2d 323, 326 (Va. 1989). By contrast, a right of action “is the 

remedial right accorded to that person to enforce a cause of action . . . [that] arises only 

when that person’s rights are infringed.” Id. The cause of action does not accrue until the 

plaintiff suffers an injury such that it “has thus ripened into a right of action.” Id. However, 

the two are not indistinguishable, and one cause of action based on the same breach of a 

plaintiff’s legal rights may produce separate harms that “give rise to separate rights of 

action that accrue at different times.” Kiser v. A.W. Chesterton Co., 736 S.E.2d 910, 915 

(Va. 2013).

This distinction has important consequences for the statute of limitations in cases 

such as this one, which involve latent diseases caused by a plaintiff’s exposure to harmful 

substances. Virginia courts interpret “injury” under section 8.01-230 to require “positive, 

physical[,] or mental hurt to the claimant, not legal wrong to him.” Locke v. JohnsManville Corp., 275 S.E.2d 900, 904 (Va. 1981). The Virginia Supreme Court has thus 

recognized that a plaintiff’s cause of action in a latent disease case does not accrue on the 

date of exposure, but instead on the date a plaintiff develops the disease, and thereby 

acquires the injury giving that plaintiff a right of action. Id. at 904–06.

While a disease might occur after a plaintiff’s exposure to a harmful substance, it 

might also occur before it is discovered. Virginia courts have repeatedly explained that a 

plaintiff’s cause of action accrues on the actual date of injury, not the date on which that 

injury is discovered by or communicated to the plaintiff. See Lo v. Burke, 455 S.E.2d 9, 

13 (Va. 1995); Comptroller of Va. ex rel. Va. Mil. Inst. v. King, 232 S.E.2d 895, 900 (Va. 

1977); Locke, 275 S.E.2d at 905–06. But see Kiser, 736 S.E.2d at 915 (discussing a specific 
12

exception to this rule for asbestos-related illnesses). This rule creates obvious difficulties 

for plaintiffs proceeding under section 8.01-243(A) who develop an illness that does not 

produce obvious or identifiable symptoms for the first two years. Regardless, a plaintiff is 

vested with a cause of action as soon as the plaintiff has an illness, even if the plaintiff

lacks symptoms. See Locke, 275 S.E.2d at 905; Lo, 455 S.E.2d at 13. Under Virginia law,

any “difficulty in ascertaining the existence of a cause of action is irrelevant.” Comptroller 

of Va., 232 S.E.2d at 900. 

Creeping diseases, such as CWP, present the additional complication that they can 

produce “successive” injuries, Joyce, 785 F.2d at 1204–05, each of which vests a plaintiff 

with a new remedial right of action, see Kiser, 736 S.E.2d at 915–17. Despite the language 

of section 8.01-230, these new rights of action do not reset the two-year statute of 

limitations under section 8.01-243(A). In Virginia, when more than one right of action

stems from the same underlying breach of a plaintiff’s legal right, those rights of action 

form part of an indivisible cause of action. Id. at 916–17. “The running of the limitations 

period [for that cause of action] will not be tolled by the fact that the . . . substantial damages 

did not occur until a later date.” Shipman v. Kruck, 593 S.E.2d 319, 323 (Va. 2004). This 

Court accordingly interprets Virginia law to bar suits based on the development of a serious 

illness when some earlier, more marginal injury already vested the plaintiff with a cause of 

action more than two years prior. See Joyce, 785 F.2d at 1203–05.

Finally, we pause to consider how courts resolve statute of limitations defenses

under Virginia law. A defendant must prove by “competent evidence ‘that pinpoints the 

precise date of injury with a reasonable degree of medical certainty’” that a plaintiff’s suit 
13

was filed outside the limitations period. Lo, 455 S.E.2d at 12 (quoting Locke, 275 S.E.2d 

at 905). In creeping-disease cases, this Court has held that a defendant need only prove

that the plaintiff’s first injury was received outside the limitations window rather than the 

specific date of injury. See, e.g., Large v. Bucyrus-Erie Co., 707 F.2d 94, 97 (4th Cir. 

1983) (“The illnesses complained of by plaintiff do not arise at a given point in time; 

instead, they result over a period of time, the beginning being unknown.”).

III.

On appeal, Adams argues that the district court failed to properly consider evidence 

concerning the onset of his occupational injury and erred in interpreting the applicable 

statute of limitations. Although Adams’s evidence might create genuine disputes about 

specific factual assertions made by Defendants, there is no genuine dispute about the only 

material question in this case: whether Adams first developed a respiratory illness outside 

the limitations period. Nor, for the following reasons, did the district court incorrectly 

interpret Virginia’s statute of limitations. This Court is therefore obligated to affirm the 

district court’s grant of summary judgment.

A.

Adams first argues that the district court incorrectly applied the summary judgment 

standard by improperly weighing or excluding multiple pieces of evidence in the record. 

Those claims are summarized as follows:
14

First, Adams claims the district court erred in basing his summary judgment ruling 

on Dr. Alam’s deposition testimony that “as of 2007 or 2009 . . . Mr. Adams had some 

degree of CWP scarring in his lungs.” See J.A. 1141. Adams disputes his expert’s opinion, 

which was based on Dr. Alam’s retrospective review of Adams’s full medical history. 

Adams argues that the CT scans Dr. Alam performed in 2007 and 2009 only revealed the 

existence of granulomas on his lungs, which are not caused by CWP.

Second, Adams argues that the district court should have excluded the testimony of 

Dr. Alam about the conclusions of NIOSH B-readers, because Dr. Alam is not himself a 

B-reader. Adams similarly believes the Court did not give sufficient weight to Dr. 

Lockey’s testimony, which casts doubt on the B-readers’ findings of Category 1 simple 

CWP. Adams also generally disputes the inclusion of NIOSH’s conclusions in the court’s 

factual findings, given that these exams were non-diagnostic.

Third, Adams contends that the district court improperly attributed the “[m]oderate 

restriction” revealed by his 2013 pulmonary function testing to occupational illness. See 

J.A. 999–1000. He believes this conclusion—which is based on Dr. Alam’s deposition 

testimony—is disputed, given Dr. Alam’s prior belief that Adams may have suffered from 

pneumonia as well as Dr. Lockey’s expert opinion that Adams might also have asthma and 

allergies. Previous doctors had also considered whether hypertension and sleep apnea were 

to blame for his shortness of breath. 

Fourth, Adams believes the district court gave “undue weight” to the consistent 

inclusion of CWP as part of the differential diagnosis and patient history in his medical 

records. Opening Br. at 17. Adams stresses that a differential diagnosis is merely “a list 
15

of diagnostic possibilities being considered by a healthcare provider,” and therefore cannot 

prove he had CWP on a particular date absent clinical correlation. Id.

Even if this evidence creates genuine disputes about specific medical findings in the 

record, Adams’s arguments mistake the nature of the dispute before the Court. As the 

district court correctly held, the only issue to be resolved on summary judgment was 

whether Adams developed CWP at some point prior to September 29, 2014—the earliest 

date on which he could have developed the disease without time-barring his September 29, 

2016 suit. The district court’s framing of the dispute is compelled by two opinions of this 

Circuit holding that defendants meets their burden under Virginia’s statute of limitations 

by proving that a slow-developing disease, like CWP, first manifested itself outside the 

statute of limitations, even if the exact date of injury is unclear. Large, 707 F.2d at 97; 

Joyce, 785 F.2d at 1205.7

Accordingly, so long as some undisputed evidence proves to a reasonable degree of 

medical certainty that Adams developed CWP prior to September 29, 2014, any disputes

7 These prior opinions may be in some tension with the language of the Virginia 

Supreme Court in Locke, given its requirement that the defendant marshal evidence that 

“pinpoints the precise date of injury with a reasonable degree of medical certainty.” 275 

S.E.2d at 905 (emphasis added). However, Large and Joyce were both decided after Locke, 

and this Court’s panel in Large explicitly interpreted Locke to only require proving the prelimitations onset of a creeping disease. Large, 707 F.2d at 97; see also St. George v. 

Pariser, 484 S.E.2d 888, 891 (Va. 1997) (“To carry his burden on the limitations plea, 

therefore, [the defendant] was required to show, with reasonable medical certainty, that 

this injury . . . occurred prior to October 21, 1991.”). The Virginia Supreme Court has not 

corrected this Court’s interpretation of state law, and we are not at liberty to overturn these 

earlier panels’ published opinions. See Brown v. McLean, 159 F.3d 898, 905 (4th Cir. 

1998).
16

over the significance of specific pieces of medical evidence are not material. And there is 

no genuine dispute that Adams developed CWP outside the limitations period. Adams’s 

own expert, Dr. Alam, testified that “usually black lung is a very slow, progressive disease

[developing over a] 10, 15 year period.” J.A. 989. According to Dr. Alam, even in rare, 

accelerated cases of the disease, it develops over five years. CWP “never occurs 

overnight.” J.A. 1026. On October 2, 2014, Adams was diagnosed with Category B 

complicated CWP. As NIOSH letters received by Adams explain, CWP progresses 

through three stages of simple CWP, followed by three stages of complicated CWP. This 

means that his disease not only progressed beyond the first stage of complicated CWP, but 

also progressed through the three initial stages of simple CWP. To fall within the 

limitations period, this must have occurred in three days, which Adams’s own counsel 

plainly conceded during the summary judgment hearing did not happen. Although the 

district court is required to make all reasonable inferences in favor of the plaintiff, Dash, 

731 F.3d at 311, it would be unreasonable to infer based on this testimony that Adams’s 

CWP developed within the limitations period. No reasonable jury could conclude 

otherwise, and therefore summary judgment is appropriate. See Anderson, 477 U.S. at 248.

Second, both Dr. Alam and Dr. Lockey testified that Adams developed CWP prior 

to September 29, 2014, and both experts examined similar medical evidence in reaching

that conclusion. Dr. Alam testified that Adams had suffered some form of occupational 

lung disease by 2009. Importantly, Dr. Alam testified that Adams’s 2012 x-ray, which 

showed “interstitial process in the lungs, slightly more impressive than January 14, 2007” 

reflected a worsening of already existing CWP. J.A. 1093–94. Therefore, Dr. Alam 
17

believes Adams’s 2013 x-ray revealed the further development of CWP-associated nodules 

on his lungs.

8 Dr. Alam also testified that Adams’s 2013 pulmonary function testing—

which indicated moderate lung restriction—was caused by exposure to coal dust.

Similarly, Dr. Lockey testified that Adams had developed CWP by 2010 or 2011. 

He based this conclusion on his review of Adams’s x-rays, which appeared relatively 

normal prior to 2010, but which showed abnormalities by 2012. Also relevant to his 

analysis was a review of Adams’s pulmonary function test results, which worsened 

between 2007 and 2018 at five times the normal rate due to aging, and which he concluded 

were primarily driven by CWP, not asthma.

In light of this evidence, there is no genuine dispute of material fact that Adams’s 

CWP first manifested itself before September 29, 2014. The only potential material dispute

created by Adams’s evidence concerns Dr. Alam’s conclusion that Adams’s 2013 

pulmonary function test reflected the existence of CWP. It is true both that Dr. Lockey 

testified that Adams could suffer from asthma and that doctors previously diagnosed him 

with sleep apnea and hypertension prior to his 2013 testing. Dr. Lockey, however,

explicitly testified that CWP, not asthma, was responsible for Adams’s decline in 

pulmonary function between 2007 and 2018.9

8 Adams argues that x-rays can never be used to diagnose CWP. Therefore, without 

clinical correlation, these x-rays do not prove the existence of the illness. However, given 

that Adams’s October 2, 2014 diagnosis is undisputed, these x-rays simply serve as 

evidence of the progression of a disease both parties already agree he has. 

9 Adams similarly argues that a pulmonary function test revealed normal diffusion

capacity in 2007 and that the district court improperly relied on a 2011 finding by Dr. 
18

Further, Dr. Lockey and Dr. Alam had the benefit of retroactively reviewing

Adams’s full medical history when forming their opinions. Based on their knowledge that 

Adams does in fact have CWP, the experts were able to interpret Adams’s earlier symptoms

and test results—including his 2013 pulmonary function test—as evidence of his 

developing CWP. The fact that earlier doctors could not have known his eventual diagnosis

when exploring other causes of Adams’s poor lung function does not create a genuine 

dispute as to the consistent medical opinion delivered by the experts in this case: Adams 

had CWP prior to September 29, 2014.

B.

Adams also makes a series of arguments urging this Court to reinterpret Virginia’s 

statute of limitations rule to forbid the hindsight review conducted by the experts. Adams 

contends that because CWP is a latent disease that changes the body in nonobvious ways,

it could not be diagnosed until the larger opacities and distortions revealed themselves in 

Adams’s 2014 x-ray. Without the advantage of retroactive review and knowledge of his 

diagnosis, Dr. Alam and Dr. Lockey would not have been able to conclude that Adams’s

pre-2014 symptoms and test results were caused by CWP. Adams claims that Defendants 

have thus improperly “bootstrap[ped]” the experts’ post-2014 opinions onto pre-2014 

Velazquez that Adams’s breathing was marked by “diffuse bronchi and dry crackles.” J.A. 

1081–82. However, this evidence cannot create a genuine, material dispute that Adams 

developed CWP before 2014, in light of expert testimony about Adams’s later x-rays in 

2012 and 2013 as well as his 2013 pulmonary function tests.
19

medical evidence that could not, itself, have demonstrated the existence of CWP to a 

reasonable degree of medical certainty. Opening Br. at 24–25.

Ultimately, Adams argues the district court erred by permitting Defendants to 

pinpoint the existence of CWP retrospectively by means of expert opinion. Such a rule

raises serious fairness concerns because it places Adams in a bind—his cause of action 

accrued and expired well before sufficiently unambiguous injuries gave him a provable 

right of action. Adams therefore argues that Virginia’s statute of limitations rule instead 

sets October 2, 2014—the date of his diagnosis—as the date on which his cause of action 

accrued, because it was the first time his illness was pinpointed to a reasonable degree of 

medical certainty as having occurred.

However, Adams’s interpretation of Virginia law resembles the sort of discovery 

rule that was explicitly rejected by Virginia’s General Assembly and that Virginia courts 

have consistently declined to read into the statute of limitations. See, e.g., Comptroller of 

Va., 232 S.E.2d at 900 (“We have followed the general rule that the applicable period of 

limitation begins to run from the moment the cause of action arises rather than from the 

time of discovery of injury . . . .”); Lo, 455 S.E.2d at 13; Locke, 275 S.E.2d at 905–06. 

Therefore, in creeping-disease cases, a cause of action may accrue—and trigger the statute 

of limitations—before a disease “manifests itself by symptoms, since it is the onset of the 

disease itself that triggers the running of the limitation period.” Lo, 455 S.E.2d at 13. 

Adams is correct that Virginia law requires proving the onset of a disease with

“competent evidence ‘that pinpoints the precise date of injury with a reasonable degree of 

medical certainty.’” Id. at 12 (citing Locke, 275 S.E.2d at 905). However, because a 
20

plaintiff can have a cause of action before developing symptoms, it logically follows that 

a defendant may pinpoint the date of injury retrospectively to a time before symptoms 

developed. As the court in Locke recognized, “expert medical testimony will [sometimes]

demonstrate the injury occurred weeks, months[,] or even years before the onset of 

symptoms. Thus, the cause of action would accrue and the limitations period would run 

from the earlier and not the later time.” 275 S.E.2d at 905 (emphasis added); see also 

Large, 707 F.2d at 97 (relying on expert testimony to retrospectively establish the date of 

injury). Adams’s insistence that we instead treat the date of his diagnosis as the accrual 

date conflates Locke’s requirement that an injury must occur for a cause to accrue with the 

requirement for how that injury must be proven. Instead, Virginia law plainly states that 

an injury can and sometimes will exist before it is discovered.

Adams’s briefing suggests that Virginia’s statute of limitations cannot be this harsh, 

because it would place him in an absurd dilemma. However, the Virginia General 

Assembly’s actions subsequent to the Locke decision suggest this outcome is intended by 

the General Assembly, even if it produces unfair results. The Virginia Supreme Court’s 

1981 decision in Locke reaffirmed the Commonwealth’s no-discovery rule and noted that 

any change to that rule “must be accomplished by the General Assembly.” 275 S.E.2d at 

905–06. In response, the General Assembly explicitly created an exception to the nodiscovery rule: four years after the Locke decision, the General Assembly amended Va. 

Code Ann. § 8.01-249 to create a discovery rule for asbestos-related diseases. See Va. 

Code Ann. § 8.01-249(4) (“In actions for injury to the person resulting from exposure to 

asbestos . . . [an action accrues when the] disease is first communicated to the person or his 
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agent by a physician.”); see also Kiser, 736 S.E.2d at 915 (discussing this amendment). 

Thus, the legislature has declined to make Adams’s claims subject to a discovery rule after 

Locke, despite doing so for a similar disease. Under Virginia law, this constitutes 

legislative acquiescence to and approval of that interpretation. Cygnus Newport-Phase 1B, 

LLC v. City of Portsmouth, 790 S.E.2d 623, 627 (Va. 2016); see also Lee-Thomas v. Prince 

George’s Cnty. Pub. Schs., 666 F.3d 244, 254 (4th Cir. 2012) (applying state law doctrine 

of acquiescence when interpreting a state statute).

Finally, our conclusion is further compelled by Virginia’s statutory scheme, which 

creates an indivisible cause of action for all rights of action that stem from a defendant’s 

breach. See Va. Code Ann. § 8.01-243(A) (“[E]very action for personal injuries . . . shall 

be brought within two years after the cause of action accrues.” (emphasis added)); Kiser, 

736 S.E.2d at 916–17. As discussed above, Adams’s cause of action accrued as soon as he 

suffered even the slightest injury caused by the inhalation of coal dust. His later 

development in 2014 of larger opacities and distortions in his lungs gave him a new right 

of action to remedy these new harms. However, as discussed above, this new or worsening 

injury did not vest him with a new cause of action that reset the statute of limitations. See

Joyce, 785 F.2d at 1204–05. Just as it did with the Commonwealth’s discovery rule, 

Virginia’s General Assembly appears to have modified the indivisible cause of action rule 

for asbestos-related illnesses. See Va. Code Ann. § 8.01-249(4) (“The diagnosis of a 

nonmalignant asbestos-related injury or disease shall not accrue an action based upon the 

subsequent diagnosis of a malignant asbestos-related injury or disease . . . .”). By leaving 

an indivisible cause of action in place for other diseases, including CWP, the legislature 
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has acquiesced to the Virginia Supreme Court’s consistent holding that the eventual 

development of more significant injuries does not provide plaintiffs like Adams with a new 

cause of action. See Cygnus Newport-Phase 1B, LLC, 790 S.E.2d at 627. Accordingly, 

this Court is bound to affirm the district court’s correct conclusion that the limitations

period did not begin to run on October 2, 2014, the date Adams first discovered he had 

CWP.

IV.

In reaching this conclusion, we would be remiss in remaining silent about the 

manifest unfairness that it poses to plaintiffs, like Adams, who suffer from latent diseases 

that cause ambiguous symptoms for the first two years or successive harms that fall outside 

the limitations window. We therefore join other state and federal courts in recognizing that 

Virginia law essentially bars certain plaintiffs from recovery. See, e.g., Joyce, 785 F.2d at 

1205 (“[T]his rule may effectively preclude recovery for serious injuries . . . . [I]ts result 

may be harsh when applied to asbestos-related or other ‘creeping disease’ cases . . . .”); 

Comptroller of Va., 232 S.E.2d at 900 (“The inequities that may arise from the general rule 

which may trigger a statute of limitations when the injury or damage is unknown or difficult 

or even incapable of discovery are apparent.”).

Adams is faced with a catch-22 from which Virginia law provides no escape. If he 

brought his claims within the two-year statute of limitations, he would have been unable to 

prove them, because doctors at the time had not clinically correlated his symptoms with 

CWP. Now that he can prove his injuries were caused by the inhalation of coal dust, the 
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claims are barred by Virginia law. It is difficult to imagine how any miner could bring a 

personal injury claim based on black lung, given that it will likely remain hidden or at least 

ambiguous throughout the two-year limitations window. Today, Adams struggles with the 

most basic activities of life, but he lacks any ability to remedy his injuries.

Perhaps at trial, Defendants would have shown that their respirators were not 

responsible for the serious harm that has befallen Adams. But Virginia law has deprived 

Adams of the ability to test the evidence in this case. The Commonwealth’s statute of 

limitations operates as a “get-out-of-jail-free” card that guarantees Adams and those like 

him will never get their day in court. Given the state legislature’s refusal to change that 

law in the face of numerous opinions spelling out its harsh consequences for those in 

Adams’s shoes, this Court can only conclude the law does so by design, not by mistake. 

We are obligated to apply the Commonwealth’s statute of limitations as it is, not as we 

would like it to be. The district court’s judgment is accordingly

AFFIRMED.