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ADVANCE SHEET HEADNOTE

May 30, 2017

2017 CO 55

No. 16SC444, England v. Amerigas Propane—Workers’ Compensation—Mutual 

Mistake of Material Fact—Colorado Workers’ Compensation Act.

 In this case, the supreme court considers whether a provision of the mandatory 

form settlement document promulgated by the Director of the Division of Workers’ 

Compensation waives an injured employee’s statutory right under section 8-43-204(1), 

C.R.S. (2016), to reopen a settlement based on a mutual mistake of material fact. The 

supreme court concludes that it does not because provisions of the form document must 

yield to statutory rights. Accordingly, the supreme court reverses the judgment of the 

court of appeals.
The Supreme Court of the State of Colorado

2 East 14th Avenue • Denver, Colorado 80203

2017 CO 55

Supreme Court Case No. 16SC444

Certiorari to the Colorado Court of Appeals

Court of Appeals Case No. 15CA1210

Petitioner:

Victor England,

v.

Respondents:

Amerigas Propane and Indemnity Insurance Company of North America.

Judgment Reversed

en banc

May 30, 2017

Attorneys for Petitioner:

Dean Neuwirth P.C.

Dean Neuwirth

 Denver, Colorado

Attorneys for Respondents:

Lee + Kinder, LLC

Joshua D. Brown

 Denver, Colorado

Attorneys for Amicus Curiae Colorado Defense Lawyers Association:

University of Colorado

Patrick T. O’Rourke

Donald A. Kaade

 Denver, Colorado

Attorneys for Amicus Curiae Colorado Department of Labor, Division of Workers’ 

Compensation:

Cynthia H. Coffman, Attorney General

Emmy A. Langley, Assistant Attorney General

 Denver, Colorado
2

Attorneys for Amicus Curiae Colorado Trial Lawyers Association:

Ogborn Mihm, LLP

Thomas Neville

 Denver, Colorado

Attorneys for Amicus Curiae Colorado Workers’ Compensation Education 

Association:

Burg Simpson Eldredge Hersh & Jardine, P.C.

John M. Connell

 Englewood, Colorado

Attorney for Amicus Curiae Pinnacol Assurance:

Harvey D. Flewelling

 Denver, Colorado

CHIEF JUSTICE RICE delivered the Opinion of the Court.

JUSTICE HOOD and JUSTICE GABRIEL do not participate.
3

¶1 This case requires us to determine whether a provision of the mandatory form 

settlement document promulgated by the Director of the Division of Workers’ 

Compensation (“Director”) waives an injured employee’s statutory right under section 

8-43-204(1), C.R.S. (2016), to reopen a settlement based on a mutual mistake of material 

fact.

1 We hold that it does not because provisions of the form document must yield to 

statutory rights. Accordingly, we reverse the judgment of the court of appeals and 

remand for further proceedings consistent with this opinion.

I. Facts and Procedural History

¶2 Petitioner Victor England was a truck driver for Amerigas Propane

(“Amerigas”). He filed a workers’ compensation claim after sustaining a serious injury 

to his shoulder in December 2012 while making a delivery for Amerigas. England

underwent two surgeries in the first half of 2013 to repair his shoulder.

¶3 In July 2013, Amerigas’s physician reported that England should reach 

maximum medical improvement (“MMI”) in two or three months. England was still in 

pain after the second surgery, but believing that the pain was part of the recovery 

process and would subside as he healed, he agreed in September 2013 to settle his 

workers’ compensation claim for $35,000.

 

1 Specifically, we granted certiorari to review the following issue:

Whether the court of appeals erred as a matter of law in interpreting the 

mandatory form settlement documents promulgated by the Division of 

Workers’ Compensation to waive an injured employee’s statutorily 

protected right to reopen a settlement based on mutual mistake of 

material fact.
4

¶4 England’s claim was governed by the Colorado Workers’ Compensation Act, 

§§ 8-40-101 to 8-47-209, C.R.S. (2016) (“Act”), which requires that settlements between 

employer and employee must be written, signed by both sides, and approved by the 

Director or an administrative law judge (“ALJ”). § 8-43-204(2)–(3). Pursuant to section 

8-43-204, the Director has promulgated a form settlement agreement (“Form”), which 

the parties are required to use to settle all claims. 7 Code Colo. Reg. 1101-3:9 (2016). In 

the instant case, the parties’ settlement agreement was consistent with the Form,

including, as relevant here, paragraphs four and six. Paragraph four, which 

incorporated the mutual mistake of material fact doctrine from section 8-43-204(1), 

provided for the right to reopen the settlement based on a mutual mistake of material 

fact, and paragraph six waived England’s right to compensation for any “unknown 

injuries.” The Director approved the settlement as required by section 8-43-204(3).

¶5 England’s pain continued after the settlement agreement was signed and 

approved. In October 2013, he sought further medical evaluation, which revealed a 

previously undiagnosed stress fracture in the scapula (shoulder blade) of England’s

injured shoulder. Up to this point, no one was aware that this fracture existed. England

claims that if he had been aware of this fracture, he would not have settled his claim.

¶6 England filed a motion to reopen the settlement on the ground that the newly 

discovered scapular fracture was a mutual mistake of material fact that justified 

reopening his workers’ compensation claim. Upon reviewing the motion, an ALJ

found: (1) none of the parties could have known about the scapular fracture when the 

claim was settled, and the parties instead believed that England was merely 
5

experiencing recovery pain on his way to MMI, when in actuality he had “an 

undisclosed and undiagnosed scapula[r] fracture”; (2) the scapular fracture was caused 

by a screw that was inserted into England’s scapula during the second of his two 

pre-settlement shoulder surgeries; (3) the scapular fracture existed when the claim was 

settled; (4) the scapular fracture was material because it necessitated more surgeries, it 

still had not been resolved, and it prevented England from returning to work; and (5) if 

England had been aware of the fracture in his scapula, he would not have settled his 

workers’ compensation case. Based on these findings, the ALJ concluded that the 

parties’ ignorance as to the scapular fracture constituted a mutual mistake of material 

fact, granted England’s motion to reopen, and awarded England temporary total 

disability benefits starting on the date of the settlement. A panel of the Industrial Claim 

Appeals Office (“ICAO”) affirmed. 

¶7 In a published, unanimous decision, a division of the court of appeals reversed. 

Amerigas Propane v. Indus. Claim Appeals Office, 2016 COA 65, ___ P.3d ___, reh’g 

denied (May 26, 2016). The division concluded that although paragraph four of the 

settlement agreement provided for the right to reopen a settlement based on a mutual 

mistake of material fact, “unknown injuries” as defined in paragraph six were carved 

out of the definition of mutual mistake of material fact. Id. at ¶ 33. The scapular

fracture, according to the division, fell within the category of “unknown injuries” 

defined in paragraph six because it was caused by a surgery to address England’s 

original injury. Id. at ¶ 35. Therefore, the division concluded, the scapular fracture 

could not serve as a basis for reopening the settlement. Id. We granted certiorari.
6

II. Standard of Review

¶8 Like other statutes, provisions in the Act are interpreted de novo. Williams v. 

Kunau, 147 P.3d 33, 36 (Colo. 2006). Additionally, interpretation of the language of a

settlement agreement is a question of law which we also review de novo. See Ad Two, 

Inc. v. City & Cty. of Denver, 9 P.3d 373, 376 (Colo. 2000); Moland v. Indus. Claim 

Appeals Office, 111 P.3d 507, 510 (Colo. App. 2004).

III. Analysis

¶9 We begin by providing an overview of the relevant portions of both the Act and 

the Form. We then conclude that a provision in the Form cannot waive an injured 

employee’s statutory right under section 8-43-204(1) of the Act to reopen a settlement 

based on a mutual mistake of material fact. Finally, we determine that a mutual 

mistake of material fact was established in this case, and consequently, England retains 

the right to reopen his claim.

A. The Workers’ Compensation Act and the Director’s Form

¶10 The Act governs employers’ payments of compensatory benefits to employees 

who have suffered work-related injuries. Whiteside v. Smith, 67 P.3d 1240, 1245 (Colo. 

2003). As discussed above, the Act allows an employer and employee to settle an

employee’s injury claim, but the settling parties must use the promulgated Form and

cannot modify its language. 7 Code Colo. Reg. 1101-3:9 (2016). Instead, the parties may 
7

only fill in their names, the date of injury, a description of the injury, and the amount of 

the settlement.2 See Form WC104, Colo. Dep’t of Labor & Emp’t (June 2016).

¶11 Two paragraphs of the Form are relevant to our analysis today: paragraph four 

and paragraph six. Paragraph four, in relevant part, states: “The parties stipulate and 

agree that this claim will never be reopened except on the grounds of fraud or mutual 

mistake of material fact.” Id. at ¶ 4. This paragraph incorporates the statutory right to 

reopen a workers’ compensation claim as provided by section 8-43-204(1) of the Act. 

That statutory provision states that a settlement agreement may be reopened “on the 

ground of fraud or mutual mistake of material fact,” even where the agreement 

otherwise provides that the claim “shall not be reopened.” § 8-43-204(1). 

¶12 Paragraph six of the Form, in turn, contains a release of claims for “unknown 

injuries.” In full, this paragraph reads:

[The injured employee] realizes that there may be unknown injuries, 

conditions, disease, or disabilities as a consequence of these alleged 

injuries or occupation diseases, including the possibility of a worsening of 

the conditions. In return for the money paid or other consideration 

provided in this settlement [the injured employee] rejects, waives and 

FOREVER gives up the right to make any kind of claim for workers’ 

compensation benefits against [the employer and its insurer(s)] for any 

such unknown injuries, conditions, diseases, or disabilities resulting from 

the injuries or occupational diseases, whether or not admitted, that are the 

subject of this settlement.

Form WC104, ¶ 6. Neither section 8-43-204(1) nor any other provision in the Act

mandates such a release.

 

2 The parties may insert additional terms in paragraph nine, but they cannot alter or 

delete the existing language in the other paragraphs.
8

¶13 The crux of this case is whether the language in paragraph six waives or limits an 

employee’s statutory right under section 8-43-204(1) to reopen based on mutual mistake 

of material fact as provided in paragraph four. We now turn to this question.

B. The Section 8-43-204(1) Right to Reopen

¶14 As noted above, section 8-43-204(1) clearly provides that workers’ compensation 

claim settlements can be reopened “on the ground of fraud or mutual mistake of 

material fact.” However, the Form cannot waive statutory rights and must yield to the 

statute. See Monfort Transp. v. Indus. Claim Appeals Office, 942 P.2d 1358, 1360 (Colo. 

App. 1997) (holding that any agency rule which conflicts with a statute is void). 

Therefore, in order to remain a valid provision of the Form, paragraph six must be 

interpreted in such a way as to be consistent with the statute.

¶15 To reach this conclusion, we first consider our decision in Padilla v. Industrial

Commission, 696 P.2d 273 (Colo. 1985). In that case, Padilla and his employer settled 

Padilla’s work-related injury claim. Id. at 275. The settlement agreement broadly 

released “any and all claims . . . of any kind or nature whatsoever, known and 

unknown” relating to the work-related injury. Id. The agreement also stated that

Padilla was “forever” precluded from bringing additional claims. Id. The Director 

approved the agreement. Id. One year later, under the then-existing version of the Act, 

Padilla moved to reopen his settled claim on the ground of mistake because his 

condition had worsened.

3 Id. The ALJ denied the motion to reopen, holding that the 

 

3 When Padilla executed the settlement, the version of section 8-43-204 in effect at that 

time was silent about whether claims resolved by settlement could be reopened. 
9

settlement agreement had waived any right to reopen. Id. at 276. The ICAO and the 

court of appeals both affirmed the ALJ. Id.

¶16 We reversed the court of appeals’ denial of Padilla’s request to reopen, holding 

that: (1) although no section of the Act expressly provided for reopening a claim that 

had been settled, the Act’s sections allowing formally adjudicated claims to be reopened 

should also apply to settled claims, id. at 276, 279–80; and (2) a settlement agreement 

could not waive the statutory right to reopen a claim, id. at 280–81. In support of the 

latter conclusion, we reasoned that the agreement’s waiver provisions must yield to 

“the very purposes of the Act and the policy expressed by [the Act’s] reopening 

provisions.” Id. Specifically, we noted that the overall purpose of the Act is the 

“beneficent” purpose of compensating injured workers; consequently, the Act’s 

“provisions are to be interpreted liberally in favor of the right of injured workers.” Id.

at 276–77. Additionally, the Act’s sections allowing formally adjudicated claims to be 

reopened “indicate a strong legislative policy to the effect that in workers’ 

compensation cases the goal of achieving a just result overrides the interest of litigants 

in achieving a final resolution of their dispute,” id. at 278, and the same statutory 

sections “represent a strong public policy” to reopen closed claims, id. at 279, 

“regardless of the manner in which the case was resolved,” id. at 280.

¶17 In response to Padilla, the General Assembly amended the Act to preclude 

reopening a settled claim if the settlement agreement had waived the right to reopen. 

 

However, other sections of the Act provided that claims resolved by formal agency 

action could be reopened, for various reasons specified in those sections. See § 8-43-303, 

C.R.S. (2016).
10

See Ch. 77, sec. 2, § 8-53-105, 1985 Colo. Sess. Laws 355, 355. However, as amended and 

as relevant here, the Act in section 8-43-204(1) allowed full and final settlements to be 

reopened in cases involving either (1) fraud or (2) mutual mistake of material fact. 

Therefore, the effect of the amendment was to restrict Padilla’s scope to these two

grounds for reopening a settlement. As such, Padilla’s reasoning still applies to these 

two grounds, which are rooted in the Act. Thus, Padilla’s holding—that workers’ 

compensation claims resolved by settlement agreement may be subsequently reopened 

even if the settlement agreement waived claims for unknown injuries—remains in force 

in cases of mutual mistake of material fact. Accordingly, we hold that paragraph six of 

the Form cannot waive or limit an employee’s statutory right to reopen his claim, 

incorporated into paragraph four, on the ground of mutual mistake of material fact. 

¶18 Instead, we conclude that paragraph six must be interpreted in such a way as to 

be consistent with the statute. To do so, we hold that paragraph six applies only to 

those “unknown injuries” that develop after a settlement agreement is signed and 

approved and paragraph four applies only to those injuries that constitute a “mutual 

mistake of material fact” and are unknown and existing before the settlement 

agreement is signed and approved. This interpretation gives full effect to each 

paragraph without generating any conflict between the paragraphs. It also is consistent 

with the principle discussed below that the doctrine of mutual mistake does not apply 

to a future fact.
11

C. Mutual Mistake of Material Fact in This Case

¶19 Here, there was a mutual mistake of material fact that provides England a right 

to reopen his claim under paragraph four. The doctrine of mutual mistake provides 

that “an agreement founded in a mutual mistake of facts that are the very basis of the 

contract will void the contract.” Carpenter v. Hill, 283 P.2d 963, 965 (Colo. 1955). A 

mutual mistake voids the contract because the contracting parties’ mutual mistake 

prevented the true meeting of the minds needed to form a contract. 17A Am. Jur. 2d 

Contracts § 201 (2016).

¶20 The doctrine of mutual mistake has three primary criteria. First, the mistake 

must be mutual, meaning “both parties must share the same [factual] misconception.” 

Cary v. Chevron, 867 P.2d 117, 118 (Colo. App. 1993). Second, the mistaken fact must 

be material, meaning that it is a fact which goes to “the very basis of the contract.” 

Carpenter, 283 P.2d at 965. In other words, the mistake of fact must relate to a material 

aspect of the contract such that, but for the mistake, the party seeking rescission would 

not have entered the contract. See Reliance Fin. Corp. v. Miller, 557 F.2d 674, 679 (9th 

Cir. 1977) (“The court must be satisfied, that but for the mistake the complainant would 

not have assumed the obligation from which he seeks to be relieved.” (quoting Roller v. 

Cal. Pac. Title Ins. Co., 206 P.2d 694, 699 (Cal. App. 1949))). Third, the mistaken fact 

must be a past or present existing one, as opposed to “a fact to come into being in the 

future.” Hailpern v. Dryden, 389 P.2d 590, 593 (Colo. 1964).

¶21 In the instant case, the parties were mutually mistaken about a material fact at 

the time they signed the settlement agreement, namely England’s unknown but existing 
12

scapular fracture. As the ALJ found, the mistake was mutual because both parties were 

unaware of the scapular fracture and instead believed that England was only 

experiencing recovery pain. The mistaken fact was material because England would 

not have settled if he had known of the scapular fracture. And it was a present existing 

fact because the scapular fracture existed at the time the settlement agreement was 

signed. Thus, England retains the right to reopen his claim based on mutual mistake of 

material fact.

IV. Conclusion

¶22 We hold that paragraph six of the Form cannot waive or limit an employee’s 

statutory right to reopen a claim, incorporated into paragraph four, on the ground of 

mutual mistake of material fact. Thus, we interpret paragraph six to be consistent with 

section 8-43-204(1) and conclude paragraph six applies only to those “unknown 

injuries” which develop after a settlement agreement is signed and approved. We also 

conclude that a mutual mistake of material fact was established in this case and 

therefore under paragraph four England has the right to reopen his claim on this basis. 

We therefore reverse the judgment of the court of appeals and remand for further 

proceedings consistent with this opinion.