F I LED

United States Court of Appeals

Tenth Circuit

June 29, 2006

Elisabeth A. Shumaker

Clerk of Court

PUBLISH

UNITED STATES COURT OF APPEALS

TENTH CIRCUIT

TERRY MINTER,

Plaintiff-Appellant,

v. No. 04-7011

PRIME EQUIPMENT COMPANY, a

Texas corporation,

Defendant-Appellee.

APPEAL FROM THE UNITED STATES DISTRICT COURT

FOR THE EASTERN DISTRICT OF OKLAHOMA

(D.C. NO. 02-CV-132-W)

John H. Tucker (Colin H. Tucker and Bradley S. Shelts with him on the briefs) of

Rhodes, Hieronymus, Jones, Tucker & Gable, Tulsa, Oklahoma for PlaintiffAppellant.

James W. Connor, Jr. (Rachel C. Mathis and Thomas D. Hird with him on the

brief) of Richards & Connor, Tulsa, Oklahoma for Defendant-Appellee.

Before LUCERO, McKAY, and McCONNELL, Circuit Judges.

McCONNELL, Circuit Judge.
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Terry Minter, the plaintiff-appellant, is a professional painter who was

severely injured after falling from an elevated work platform. He filed a personal

injury lawsuit against the manufacturer and distributor of the work platform. 

Although his complaint centered on design and manufacturing defect claims, a

series of procedural maneuvers before trial left him with only a failure to warn

claim against the distributor. The jury found for the defendant on the failure to

warn claim. Mr. Minter appeals that judgment, as well as the district court’s

ruling that left him with only one claim. We must decide whether the district

court abused its discretion by dismissing the plaintiff’s product liability claim

against the distributor for untimeliness and lack of notice and by not allowing an

amendment to the complaint; whether the district court wrongfully excluded from

trial the evidence of the distributor’s subsequent remedial measures; and whether

the district court improperly allowed evidence of comparative negligence into a

strict liability failure to warn case. 

We affirm in part, reverse in part, and remand for new proceedings in

accordance with this opinion. 

I. BACKGROUND

Terry Minter was hired to work as a painter at a construction site in Tulsa,

Oklahoma. On the morning of July 14, 1996, he was using a “scissor lift”—a

type of industrial lift that raises and lowers a platform used for work

positioning—to enable him to paint the underside of a roof at the site. While
According to the workers who came to Mr. Minter’s aid after his fall, the 1

chainlink closure on the lift was not latched. Mr. Minter testified that he

remembered closing it, but his memory of the accident was limited due to the

severe head injury he suffered from the fall. At trial, Mr. Minter argued that he

latched the chainlink entry, but the latch must have jammed. Prime Equipment

argued that Mr. Minter simply failed to latch the chainlink entry. This dispute is

irrelevant for purposes of Mr. Minter’s appeal. 

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working from atop the scissor lift, Mr. Minter accidentally stepped off the side of

the lift platform and fell twenty feet to the ground. The impact fractured his

skull, damaged his spinal cord, and resulted in permanent paralysis from the waist

down. 

Mr. Minter maintains that his accident was caused by a defect in the scissor

lift. At the time of the incident, he was using a 1987 “Barecat” model scissor lift

manufactured by Economy Company (“Economy”), a foreign corporation. The

Barecat lift was designed to have a solid metal guardrail around the entire

perimeter of the lift platform. On the lift Mr. Minter was using, one of the sides

had a chainlink closure instead of a solid guardrail. Mr. Minter failed to properly

latch the chainlink closure on the morning of the accident, which allowed him to 1

step unintentionally off the platform and fall to the ground. The gravamen of the

lawsuit is that the solid guardrail is a necessary part of the Barecat scissor lift’s

fall protection system because it is welded in place and cannot be mistakenly left

open by the user. Mr. Minter argues that if there had been a solid guardrail at the
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lift’s entrance instead of the chainlink closure, his accident would not have

happened. 

The State Court Proceedings

On April 2, 1997, Mr. Minter filed a personal injury suit in the Tulsa

County District Court in Oklahoma. Case No. CJ-97-01615. His complaint

asserted products liability and negligence claims against the manufacturer,

Economy, for failure to use reasonable care in designing, manufacturing,

inspecting, and testing the scissors lift, and for failure to warn of defects in the

lift. It also asserted strict liability and negligence claims against Appellee Prime

Equipment Company (“Prime Equipment”), a Texas-based corporation that leases,

sells, and services Economy machinery. The pleadings named four other

defendants as well: G&G Leasing, the owner of the lift; Marrs Electric, Inc., the

party leasing the lift at the time of the accident; Manhattan Construction, Inc., the

general contractor on the site; Sundial Painting, Inc., Mr. Minter’s employer; and

Silverado Foods, Inc., the owner of the building where Mr. Minter was working. 

At the time he filed the lawsuit, the plaintiff believed that Prime

Equipment’s role in the accident was limited to its maintenance and repair work

on the lift. He therefore based his claim against Prime Equipment on the

company’s alleged failure to properly “inspect, repair, and maintain the scissors

lift” when it was brought in for an annual safety inspection, in addition to its

alleged failure to warn. Appellant’s App. 158. During discovery, however, the
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plaintiff learned that Prime Equipment had owned the scissor lift between 1987,

the year the lift was manufactured, and August 1991, when Prime Equipment sold

the lift to G&G Leasing. Prime Equipment was therefore in the chain of

distribution for purposes of the manufacturer product liability claim against

Economy. 

On July 8, 1998, Mr. Minter amended his complaint to include a retailer

product liability claim against Prime Equipment. Prime Equipment disclaimed

any responsibility for removing the solid guardrail, and one of its employees

testified that Prime Equipment bought the lift from Economy with the chainlink

entry already installed. The plaintiff responded that, under Oklahoma law, Prime

Equipment was “liable under the theory of manufacturer’s product liability”

because “[t]he liability of the manufacturer and distributor/retailer is coextensive,

even though the latter may not be responsible for the existence or presence of a

defect.” Appellant’s App. 194.

Prime Equipment defended itself against both the retailer product liability

claim and the negligence claim. It responded to the product liability claim by

challenging the qualifications and testimony of the only expert witness to testify

on behalf of Mr. Minter that the lift was defective. Prime Equipment also

introduced its own expert witnesses to testify that the lift was neither defective

nor unreasonably dangerous. Those defense witnesses opined that the lift was

safe when used properly, and that the American National Standard Institute’s
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(ANSI) voluntary industry standards did not require solid guardrails until 1991,

several years after the subject scissor lift was manufactured. Prime Equipment

also presented evidence that Mr. Minter caused his own injuries; namely, that he

failed to latch the chainlink closure or use a safety harness. Prime Equipment

also filed a cross claim against Economy seeking indemnity for any liability

arising out of a product liability judgment. 

In response to the negligence claims, Prime Equipment relied on its defense

to the product liability claim, and also prepared defenses based on comparative

negligence and assumption of risk. In this connection, Prime Equipment planned

to introduce evidence of Mr. Minter’s history of marijuana use during work hours.

Mr. Minter admitted during his deposition that he “occasionally” consumed

marijuana while at work, and his medical report from after the accident showed

that he had THC metabolites in his urine, which indicate recent exposure to

marijuana. Mr. Minter testified that he was sober at the time of the accident and

that the THC metabolites in his urine were from using marijuana two days before

his fall. The defendants intended to introduce the evidence at trial, however, and

let a jury decide whether Mr. Minter was intoxicated on the morning of the

accident.

The state court never had an opportunity to address the merits of Mr.

Minter’s product liability and negligence claims. After four years of litigation,

the plaintiff settled with G&G Leasing, Manhattan Construction, Sundial Painting
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and Silverado Foods. Once those parties were dropped from the litigation, there

was complete diversity of citizenship between the plaintiff and the defendants. On

March 20, 2001, the plaintiff voluntarily dismissed his state court complaint

against the two remaining defendants, Prime Equipment and Economy, in order to

refile in federal court. 

The Federal District Court Proceedings

Mr. Minter retained new counsel and refiled in the United States District

Court for the Eastern District of Oklahoma on March 20, 2002, exactly one year

after the voluntary dismissal of his state court action. The federal complaint was

significantly shorter than his state court complaint had been. Instead of

compartmentalizing his various claims into categories of negligence, strict

liability, and product liability, the federal complaint simply stated that Mr.

Minter’s injuries were caused by “defects in the design and manufacture of a

scissor lift designed, manufactured and sold by Economy,” and by “the failure of

Prime Equipment Co., the owner, to properly inspect, repair and maintain the

lift.” Complaint 1. It also alleged that both defendants had failed “to warn Mr.

Minter of dangers in the subject scissor lift.” Id. 

In what turns out to be an important fact in this appeal, Mr. Minter’s

federal complaint did not expressly set forth a product liability claim against

Prime Equipment based on the company’s alleged responsibility for alteration of

the lift’s guardrail system. The complaint did refer to Prime Equipment as having
There appears to have been some confusion at first as to whether Prime 2

Equipment still owned the lift at the time of the accident, or whether it had sold

the lift to G&G Leasing in 1991. In either event, Prime Equipment would still be

strictly liable under a product liability theory. See Allenberg v. Bentley Hedges

Travel Serv., Inc., 22 P.3d 223, 227–28 (Okla. 2001). 

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been “the owner” of the lift, which put Prime Equipment in the chain of 2

distribution of his product liability claim against Economy. This might arguably

have been sufficient under the liberal pleading standards of Federal Rule of Civil

Procedure 8 to provide notice of a retailer product liability claim against Prime

Equipment. But there is no explicit mention in the complaint of a product

liability claim based on alterations made to the lift after its manufacture. 

On June 10, 2002, the parties submitted a Planning Meeting Report to the

district court. The Report contained a summary of Mr. Minter’s claims. This,

too, made no mention of either a retailer or alteration product liability claim

against Prime Equipment. The Report read as follows:

Summary of Claims:

Against defendant Prime Equipment Co.: Failure to inspect, repair

and maintain scissors lift. 

Failure to warn.

Against defendant Economy Co.: Defective design and

manufacture of scissors

lift. Failure to warn. 

Appellee’s Supp. App. 3. Similarly, in his interrogatory answers, Mr. Minter

based his claim against Prime Equipment on its alleged failure “to properly

inspect, repair and maintain the scissor lift” rather than on a product liability
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theory. Id. at 37–38. The plaintiff did, however, describe his negligent repair

and maintenance claim as predicated on the fact that the scissor lift, “as provided

to [him,] was in a condition” that “was contrary to established safety standards”

because it had “a detachable chain link fitted in place of a solid steel guardrail.” 

Id. 

Once the case was in federal court, all three parties agreed to use the

discovery material produced in the state court action. Mr. Minter and Prime

Equipment also introduced additional expert witness testimony regarding the

safety of the lift. The plaintiff’s new expert claimed that the replacement of the

solid guardrail with a chainlink closure rendered the lift unreasonably dangerous

and defective. Prime Equipment filed reports from two new expert witnesses who

stated that the lift was “safe for its intended use”; that the chainlink modification

“did not violate any ANSI or OSHA Standards applicable to the lift” at the time

of manufacture; that the lift was “not defective [when] equipped with . . . properly

used access point chains” instead of a solid guardrail; and that Mr. Minter caused

the accident. Appellant’s App. 42–43, 50–51. 

Shortly before the scheduled start of trial, the defendants came forward

with a new revelation about the history of the scissor lift’s guardrail system. 

Throughout the preceding five years of litigation, Prime Equipment had always

maintained that the manufacturer, Economy, was responsible for installing the

chainlink entry on the lift. On June 12, 2003, however, three weeks before the
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scheduled start of trial, Prime Equipment and Economy entered a Joint Stipulation

stating that Economy was not responsible for the missing solid guardrail at the

lift’s entrance. The Joint Stipulation stated that the “Scissor Lift was

manufactured by the Defendant, Economy Company, with four solid top rails,”

and that the “scissor lift’s condition was substantially and materially altered after

the lift left Defendant Economy’s possession and was sold . . . .” Appellant’s

App. 73. Moreover, Prime Equipment produced a new expert witness report

along with the Joint Stipulation stating that the lift was manufactured with a solid

guardrail around the entire perimeter of the lift platform. At the same time, Prime

Equipment filed an evidentiary motion that stated that “Plaintiff is pursuing Prime

[Equipment] on a negligence theory only.” Appellee’s Supp. App. 10. In

combination, these positions had the potential to erase from the litigation Mr.

Minter’s product liability claim based on the allegedly defective guardrail system:

the Joint Stipulation absolved Economy of responsibility and the evidentiary

motion took the position that any responsibility that Prime Equipment might have

for altering the guardrail system was beyond the scope of plaintiff’s negligence

theory. 

Six days after the defendants filed the Joint Stipulation, the district court

unexpectedly transferred the case to a different Judge. As a part of the transfer,

the district court struck all of the pending motions and scheduled dates previously

set in the case. A status conference was held before the new judge on July 1,
The parties made a handwritten adjustment to the case number listed on 3

the Report, indicating that the case had been assigned to a new judge, but

otherwise left the original Planning Meeting Report unchanged. 

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2003, at which time the court ordered that all previously decided motions in the

case be re-urged before the court. The court set the deadline for amendments to

the pleadings for July 16, 2003, and scheduled jury selection for December 1,

2003 and the start of trial for December 15, 2003.

The parties resubmitted their Report on the Planning Meeting on July 7,

2003. The new Report was a copy of the one filed a year earlier, and therefore 3

included the “Summary of Claims” section that failed to mention an alteration

product liability claim against Prime Equipment. 

On October 30, 2003, the parties filed their evidentiary motions. Mr.

Minter filed motions in limine to exclude evidence of his marijuana use and his

failure to wear a hard hat or safety belt on the day of the accident. Prime

Equipment filed a motion to exclude evidence that it had replaced the chainlink

closure with a solid guardrail after the accident. In that motion, Prime Equipment

again stated that “Plaintiff is pursuing Prime [Equipment] on a negligence theory

only.” Appellee’s Supp. App. 19. 

The parties met in mid-November to discuss jury instructions and draft a

proposed pretrial order. At that meeting, the plaintiff notified Prime Equipment

that it intended to include a product liability claim against Prime Equipment for
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altering the guardrail on the lift. Prime Equipment told the plaintiff that it would

object to inclusion of that claim. 

The parties submitted their proposed pretrial order to the district court on

November 24, 2003, two hours before the pretrial conference. The proposed

order contained the plaintiff’s claim that Prime Equipment “materially altered the

subject scissor lift by removal of the [] solid guardrail safety feature rendering the

product defective and unreasonably dangerous at the time of sale.” Pretrial Order

3. It also contained Prime Equipment’s objection to the claim as a “belated

attempt to add a products liability claim against it, for the very first time in th[e]

Pretrial Order.” Id. at 6. The district court did not sign the pretrial order at that

time. 

At the conclusion of the pretrial conference, the district court issued its

ruling on the pending evidentiary motions. The court denied the plaintiff’s

motion to exclude evidence of his marijuana use on the ground that it was

relevant for evaluating Prime Equipment’s comparative negligence and

assumption of risk defenses. It also denied the plaintiff’s motion to exclude

evidence that he was not wearing a hard hat or safety belt at the time of the

accident, holding that such evidence was relevant “to show Plaintiff’s conduct in

the workplace.” The court granted Prime Equipment’s motion to exclude

evidence of its subsequent remedial measures to the lift. 
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On the morning of December 1, 2003, with the dispute over the alteration

product liability claim still unresolved, the district court signed and entered the

pretrial order. It contained the plaintiff’s product liability claim against Prime

Equipment arising from the “material alterations” to the lift, along with a motion

by Prime Equipment to strike the claim. The pretrial order also specified that the

parties would not dispute that the lift was “manufactured and sold by Economy

Co. with a solid guardrail around entire upper perimeter of the scissor lift

platform,” or that Prime Equipment “sold the scissor lift to G&G Leasing” with

“the solid guardrail . . . removed from the entry end and replaced with a [] chain

entry.” Appellant’s App. 86. 

After the district court entered the pretrial order into the record, the

plaintiff announced that he was voluntarily dismissing his negligence claim

against Prime Equipment. He then asked the district court to reconsider its ruling

on the “very prejudicial” marijuana evidence, which he argued was irrelevant to

the product liability claims. Prime Equipment responded that because all of the

claims against it were based in negligence, and because the plaintiff had just

dismissed all of his negligence claims, Prime Equipment should be dismissed

from the lawsuit. The court took all of these matters under consideration. 

On December 4, 2003, three days after voir dire, the court heard arguments

regarding the status of the plaintiff’s remaining claims against Prime Equipment

and Economy. At the start of the hearing, the plaintiff stipulated to a dismissal of
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his design and manufacturing product liability claims against Economy,

explaining that the evidence produced by both defendants now showed that

Economy had manufactured and sold the lift with solid guardrails on all four

sides. The only claim remaining against Economy was a product liability claim

for failure to provide adequate warnings on the lift. 

On December 12, 2003, three days before the start of trial, the district court

ruled on the outstanding motions. It granted the plaintiff’s motion to exclude the

marijuana evidence. It also allowed Mr. Minter to proceed to trial against Prime

Equipment with his failure to warn claim, which the court ruled was based on a

product liability theory. However, the court granted Prime Equipment’s motion

to strike the alteration product liability claim, explaining that “any claim now

asserted by Plaintiff for products liability stemming from the alteration of the

subject lift is deemed to have never been a part of this action.” Order 6. The

court determined that none of the plaintiff’s filings before the pretrial order

provided notice of a product liability claim against Prime Equipment for altering

the lift. It declared that the prejudice to Prime Equipment that would arise from

allowing the claim is “obvious.” Id. at 5. The court noted that “[t]he assertion of

this claim [first] became apparent when the parties attempted to formulate a

Pretrial Order. Contrary to this Court’s Scheduling Order, [the] proposed Pretrial

Order . . . was not submitted to this Court until two hours before the scheduled

Pretrial Conference.” Id. at 5. Moreover, Prime Equipment had already entered
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into a Joint Stipulation with Economy stating that the scissor lift left Economy’s

control with all four solid guardrails in place, which meant that Prime Equipment

could not file a cross-claim against Economy as it did in the underlying state

court case. The court concluded that “[i]t is unlikely that Prime [Equipment]

would have taken this somewhat curious measure unless it believed that a

products liability claim had not been stated against it.” Id. at 6. 

The Trial

Mr. Minter settled with Economy on the eve of trial. When the jury trial

began on December 15, 2003, the only claim remaining in the action was

therefore against Prime Equipment for failure to provide adequate warning of

defects in the lift.

Before the start of opening arguments, the plaintiff tried again to add a

product liability claim against Prime Equipment based on alterations made to the

lift. He filed a Federal Rule of Civil Procedure 15(b) motion for an amendment

to conform to the evidence, arguing that the amendment was “necessary to carry

out [his] claim for relief” and would “not prejudice Prime [Equipment]’s defense

of the products claim.” Appellant’s App. 262. The court determined that it was

unable to rule on his Rule 15(b) motion at that time. Rule 15(b) authorizes the

amendment of pleadings to conform to evidence presented at trial, see Fed. R.

Civ. P. 15(b), and the plaintiff filed his motion before any evidence had been
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presented. The court told the parties that it would reserve its consideration of the

motion until later in the case. 

With no real alternative left, the plaintiff proceeded to trial with only a

failure to warn claim against Prime Equipment. In presenting his case to the jury,

the plaintiff argued that because the guardrail system had been altered, the

original warnings posted by the manufacturer were no longer adequate, and Prime

Equipment had an obligation to post additional warnings. As a result, much of

the case still concerned the removal of the solid guardrail and whether the

chainlink closure was unreasonably dangerous, even though the plaintiff could not

assert an alteration product liability claim. Prime Equipment consistently

objected to the introduction of evidence regarding the alteration on the ground

that it was irrelevant to the failure to warn claim. The district court usually

overruled the objection, but in each case it noted that the evidence was restricted

to Mr. Minter’s failure to warn claim. At the close of the plaintiff’s case, the

court denied the plaintiff’s Rule 15(b) motion for leave to amend the pleadings to

conform to the evidence. 

Prime Equipment then proceeded to put on its defense. It called a number

of rebuttal witnesses who testified about the safety of the lift and adequacy of the

posted warnings. Prime Equipment also presented evidence that Mr. Minter had

failed to latch the chainlink closure, wear a hard hat, or use a safety belt. During

closing arguments, Prime Equipment used this evidence to argue that Mr. Minter
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was responsible for his own injuries: “if Mr. Minter had latched the chains and/or

put on the safety belt, the accident would not have occurred.” Appellant’s App.

572. 

On December 18, 2003, the jury returned a verdict in favor of Prime

Equipment on the failure to warn claim. The court entered the judgment on

December 22, 2003. The plaintiff timely filed his notice of appeal.

Appeal

Mr. Minter raises four issues on appeal. The first two relate to his

alteration product liability claim against Prime Equipment: He asserts that the

district court erred by granting Prime Equipment’s motion to strike the product

liability claim from the pretrial order, and that it erred again when it denied his

Rule 15(b) motion to amend the pleadings to conform to the evidence. The

second two issues relate to the district court’s evidentiary rulings: The plaintiff

contends that the court wrongfully excluded the evidence of Prime Equipment’s

subsequent remedial measures and that it improperly admitted the evidence that

he failed to wear a hard hat or safety belt on the day of the accident. 

II. DISCUSSION

A. Amendment to the Pleadings

Mr. Minter’s appeal centers on the district court’s decision not to permit

him to pursue an alteration product liability claim against Prime Equipment. 

Procedurally, this question arose in two orders of the district court: the order
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striking the plaintiff’s products liability claim from the pretrial order, and the

order denying his Rule 15(b) motion to amend the complaint to conform to the

evidence. Mr. Minter raises both issues on appeal, but needs to prevail on only

one. We address his argument that the district court erred in striking the

alteration product liability claim from the pretrial order. For purposes of this

opinion, we assume without deciding, that Mr. Minter did not properly plead the

alteration product liability claim in his federal court complaint, and that the

proposed pretrial order was the first time Mr. Minter raised the alteration claim. 

Federal Rule of Civil Procedure 15(a) provides that, after a responsive

pleading has been served, a party may amend its pleading “only by leave of court

or by written consent of the adverse party.” The Rule specifies that “leave shall

be freely given when justice so requires.” Although the plaintiff included his

products liability claim against Prime Equipment in the proposed pretrial order

without filing a formal Rule 15(a) motion to amend the complaint, “[w]hen an

issue is set forth in the pretrial order, it is not necessary to amend previously filed

pleadings because the pretrial order is the controlling document for trial.” Wilson

v. Muckala, 303 F.3d 1207, 1215 (10th Cir. 2002) (internal quotation marks

omitted). Consequently, Mr. Minter’s attempt to add a new claim to the pretrial

order was the equivalent of asking leave to amend his complaint, and must be

evaluated by the court under the standards set forth in Rule 15(a). See Wilson,
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303 F.3d at 1215; 6A Charles Alan Wright, Arthur R. Miller & Mary Kay Kane,

Federal Practice and Procedure § 1525 (2d ed. 1990). 

“[T]he grant of leave to amend the pleadings pursuant to Rule 15(a) is

within the discretion of the trial court,” Zenith Radio Corp. v. Hazeltine Research,

Inc., 401 U.S. 321, 330 (1971), and we will not reverse the court’s decision

“absent an abuse of discretion.” Wessel v. City of Albuquerque, 299 F.3d 1186,

1197 (10th Cir. 2002) (internal quotation marks omitted). But the Rule itself

states that “leave shall be freely given when justice so requires.” Fed. R. Civ. P.

15(a). The purpose of the Rule is to provide litigants “the maximum opportunity

for each claim to be decided on its merits rather than on procedural niceties.” 

Hardin v. Manitowoc-Forsythe Corp., 691 F.2d 449, 456 (10th Cir. 1982). In

Foman v. Davis, 371 U.S. 178 (1962), the Supreme Court held: 

If the underlying facts or circumstances relied upon by a plaintiff may be a

proper subject of relief, he ought to be afforded an opportunity to test his

claim on the merits. In the absence of any apparent or declared

reason—such as undue delay, bad faith or dilatory motive on the part of the

movant, repeated failure to cure deficiencies by amendments previously

allowed, undue prejudice to the opposing party by virtue of allowance of

the amendment, futility of amendment, etc.—the leave sought should, as the

rules require, be “freely given.” 

Id. at 182 (quoting Fed. R. Civ. P. 15(a)); see also Duncan v. Manager, Dept. of

Safety, 397 F.3d 1300, 1315 (10th Cir. 2005); Frank v. U.S. West, 3 F.3d 1357,

1365 (10th Cir. 1993). The district court struck Mr. Minter’s alteration product

liability claim from the pretrial order on the grounds that it was prejudicial and
Neither party has argued that Rule 16(b) is relevant to this question. Some 4

Circuits hold that a party seeking to amend the pleadings, after the deadline set

for such amendments in the scheduling order, must satisfy a “good cause”

requirement. See, e.g., Parker v. Columbia Pictures Indus., 204 F.3d 326, 340

(2d Cir. 2000); Hawthorne Land Co. v. Occidental Chem. Corp., 431 F.3d 221,

227 (5th Cir. 2005); Leary v. Daeschner, 349 F.3d 888, 909 (6th Cir. 2003); In re

Milk Prods. Antitrust Litig., 195 F.3d 430, 437–38 (8th Cir. 1999); Johnson v.

Mammoth Recreations, Inc., 975 F.2d 604, 607–08 (9th Cir. 1992). This requires

the moving party to show that it has been diligent in attempting to meet the

deadlines, which means it must provide an adequate explanation for any delay. 

See Parker, 204 F.3d at 340–41; Hawthorne, 431 F.3d at 228; Leary, 349 F.3d at

907; In re Milk Prods., 195 F.3d at 437–38; Johnson, 975 F.2d at 609–10. This

Circuit adopted a similar interpretation of Rule 16(b)’s “good cause” requirement

in the context of counterclaims asserted after the scheduling order deadline, SILFLO, Inc. v. SFHC, Inc., 917 F.2d 1507, 1518–19 (10th Cir. 1990), but has not

done so in the context of an amendment to the complaint. 

We do not decide whether a party seeking to amend its pleadings after the

scheduling order deadline must show “good cause” for the amendment under Rule

16(b) in addition to the Rule 15(a) requirements. Neither party raises the

question, and given the rough similarity between the “good cause” standard of

Rule 16(b) and our “undue delay” analysis under Rule 15, it would not affect the

outcome of this case.

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untimely. Prejudice and timeliness are obviously closely related, but we will

evaluate each.4

1. Timeliness

In Foman, the Supreme Court listed “undue delay” as one of the

justifications for denying a motion to amend. 371 U.S. at 182. Emphasis is on

the adjective: “Lateness does not of itself justify the denial of the amendment.” 

R.E.B., Inc. v. Ralston Purina Co., 525 F.2d 749, 751 (10th Cir. 1975). Rule

15(a) does not restrict a party’s ability to amend its pleadings to a particular stage

in the action. Fed. R. Civ. P. 15(a); see also 6 Wright, Miller & Kane, Federal
This is the majority rule, followed by the Second, Fourth, Fifth, Sixth, 5

Seventh, Eighth, Ninth and D.C. Circuits. See Block v. First Blood Assocs., 988

F.2d 344, 350 (2d Cir. 1993) (“Mere delay, however, absent a showing of bad

faith or undue prejudice, does not provide a basis for a district court to deny the

right to amend.” (internal quotation marks omitted)); Edwards v. City of

Goldsboro, 178 F.3d 231, 242 (4th Cir. 1999) (“Delay alone is an insufficient

reason to deny leave to amend. Rather, the delay must be accompanied by

(continued...)

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Practice and Procedure § 1488 (2d ed. 1990). However, “[a] party who delays in

seeking an amendment is acting contrary to the spirit of the rule and runs the risk

of the court denying permission because of the passage of time.” Id. The longer

the delay, “the more likely the motion to amend will be denied, as protracted

delay, with its attendant burdens on the opponent and the court, is itself a

sufficient reason for the court to withhold permission to amend.” Steir v. Girl

Scouts of the USA, 383 F.3d 7, 12 (1st Cir. 2004); see also USX Corp. v.

Barnhart, 395 F.3d 161, 167 (3d Cir. 2004) (“[D]elay alone is an insufficient

ground to deny leave to amend. At some point, however, delay will become

undue, placing an unwarranted burden on the court, or will be become prejudicial,

placing an unfair burden on the opposing party.” (internal citations and quotation

marks omitted)). 

The courts of appeal are not in agreement regarding the showing necessary

to establish “undue” delay. Some circuits hold that an amendment may be denied

for undue delay only if the trial court finds prejudice, bad faith, futility, or (in

some circuits) a substantial burden on the court. This Circuit, however, focuses 5
(...continued) 5

prejudice, bad faith, or futility.”) (internal citation omitted); Mayeaux v. La.

Health Servs. & Indem. Co., 376 F.3d 420, 427 (5th Cir. 2004) (“[D]elay alone is

an insufficient basis for denial of leave to amend: The delay must be undue, i.e.,

it must prejudice the nonmoving party or impose unwarranted burdens on the

court.”); Wade v. Knoxville Utils. Bd., 259 F.3d 452, 458–59 (6th Cir. 2001)

(“Delay by itself is not sufficient reason to deny a motion to amend. Notice and

substantial prejudice to the opposing party are critical factors in determining

whether an amendment should be granted.”); Doherty v. Davy Songer, Inc., 195

F.3d 919, 922 (7th Cir. 1999) (“[M]ere delay, without a showing of prejudice, is

not sufficient to deny the amendment.”); Doe v. Cassel, 403 F.3d 986, 991 (8th

Cir. 2005) (“Delay alone is not enough to deny a motion to amend; prejudice to

the nonmovant must also be shown.” (internal quotation marks omitted)); Bowles

v. Reade, 198 F.3d 752, 758 (9th Cir. 1999) (“Undue delay by itself . . . is

insufficient to justify denying a motion to amend . . . [absent] a contemporaneous

specific finding of prejudice to the opposing party, bad faith by the moving party,

or futility of amendment.”); Atchinson v. Dist. of Columbia, 73 F.3d 418, 426

(D.C. Cir. 1996) (“Consideration of whether delay is undue, however, should

generally take into account the actions of other parties and the possibility of any

resulting prejudice.”).

-22-

primarily on the reasons for the delay. We have held that denial of leave to

amend is appropriate “when the party filing the motion has no adequate

explanation for the delay.” Frank v. U.S. West, 3 F.3d 1357, 1365–66 (10th Cir.

1993); see also Durham v. Xerox Corp., 18 F.3d 836, 840 (10th Cir. 1994)

(“[U]nexplained delay alone justifies the district court’s discretionary decision.”);

Fed. Ins. Co. v. Gates Learjet Corp., 823 F.2d 383, 387 (10th Cir. 1987) (“Courts

have denied leave to amend in situations where the moving party cannot

demonstrate excusable neglect. For example, courts have denied leave to amend
This approach is also followed by the First, Third, and Eleventh Circuits. 

6

See Hayes v. New England Millwork Distribs., Inc., 602 F.2d 15, 19–20 (1st Cir.

1979) (“[W]here, as here, a considerable period of time has passed between the

filing of the complaint and the motion to amend, courts have placed the burden

upon the movant to show some valid reason for his neglect and delay.” (internal

quotation marks omitted)); Arthur v. Maersk, Inc., 434 F.3d 196, 204 (3d Cir.

2006) (“When a party fails to take advantage of previous opportunities to amend,

without adequate explanation, leave to amend is properly denied.”); Andrx

Pharm., Inc. v. Elan Corp., 421 F.3d 1227, 1237 (11th Cir. 2005) (“We agree

with the district court that [Plaintiff’s] explanations for its delay in filing for

leave to amend do not demonstrate that justice required the grant of the motion to

amend.”). 

-23-

where the moving party was aware of the facts on which the amendment was

based for some time prior to the filing of the motion to amend.”).6

Courts will properly deny a motion to amend when it appears that the

plaintiff is using Rule 15 to make the complaint “a moving target,” Viernow v.

Euripides Dev. Corp., 157 F.3d 785, 800 (10th Cir. 1998), to “salvage a lost case

by untimely suggestion of new theories of recovery,” Hayes v. Whitman, 264 F.3d

1017, 1027 (10th Cir. 2001), to present “theories seriatim” in an effort to avoid

dismissal, Pallottino v. City of Rio Rancho, 31 F.3d 1023, 1027 (10th Cir. 1994),

or to “knowingly delay[] raising [an] issue until the ‘eve of trial,’” Walters v.

Monarch Life Ins. Co., 57 F.3d 899, 903 (10th Cir. 1995). 

Mr. Minter attempted to assert an alteration product liability claim against

Prime Equipment just three weeks before the scheduled start of trial; and the

district court took note of his tardiness when it struck the amended claim from the
-24-

pretrial order. Courts “do not normally expect to see claims or defenses not

contained in the pleadings appearing for the first time in the pretrial order.”

Wilson v. Muckala, 303 F.3d 1207, 1215–16 (10th Cir. 2002). In this case,

however, the plaintiff has provided an adequate explanation for the delay, and

therefore his alteration product liability claim is not “untimely” or “unduly

delayed.” 

When the plaintiff filed his complaint on March 20, 2002, the evidence

supplied by the defendants during discovery in the state case led him to believe

that Economy had manufactured and sold the scissor lift in a defective condition. 

For the first five years of this litigation, Prime Equipment maintained that it had

bought the lift from Economy without the solid guardrail, and presented evidence

to that effect. In accordance with this apparent state of the facts, the strippeddown complaint filed in federal court included defective design and

manufacturing claims against Economy, while holding Prime Equipment

responsible for negligent maintenance and repair (in addition to suing both for

insufficient warnings). On May 21, 2003, however, one week after the close of

discovery, Economy submitted an expert witness report stating that the lift’s

guardrail system had been altered sometime after leaving its control. Within a

month, Prime Equipment reversed its position and stipulated that Economy

manufactured and sold the scissor lift with four solid guardrails. The plaintiff’s

attempt to assert a new claim in the pretrial order—to shift from a manufacturer
 When the plaintiff asserted his products liability claim in the pretrial 7

order, Prime Equipment objected on the ground that it was a “belated attempt to

add a products liability claim against it, for the very first time.” Pretrial Order 6. 

The plaintiff responded that his complaint fairly encompassed the claim because it

identified both Prime Equipment and Economy as “sellers of the scissor lift,” and

therefore “alleged facts to support recovery [from Prime Equipment] based upon

products liability.” Appellant’s App. 243–44. 

-25-

product liability claim against Economy to an alteration product liability claim

against Prime Equipment—was a response to these late disclosures from Prime

Equipment and Economy. Consequently, this case is distinguishable from those

where courts denied leave to amend because the “plaintiff was aware of all the

information on which his proposed amended complaint was based prior to filing

the original complaint.” McKnight v. Kimberly Clark Corp., 149 F.3d 1125, 1130

(10th Cir. 1998). 

During oral argument, Prime Equipment argued that the amendment was

untimely because Mr. Minter waited more than six months after he learned of the

Joint Stipulation before asserting the alteration product liability claim against it. 

The record shows that the plaintiff delayed in asserting the alteration product

liability claim against Prime Equipment because he believed it was already fairly

encompassed by his pleadings. Indeed, on appeal the plaintiff continues to take 7

that position, arguing that the district court erred in striking the products liability

claim from the pretrial order. Although we do not reach that argument, in light of

the liberal pleading requirements of Rule 8(a) we consider it a colorable
-26-

argument. In retrospect, the plaintiff could have avoided this entire controversy if

he had filed a formal motion to amend his complaint soon after the defendants

entered into the Joint Stipulation. Nonetheless, his assumption regarding the

scope of his original pleading constitutes an excusable cause for the delay,

especially in light of the defendant’s own dilatoriness in waiting until discovery

was closed and the trial was shortly scheduled to begin to spring the fact that it

was changing its position regarding a key fact in the case. Consequently, Mr.

Minter’s alteration product liability claim cannot be considered “untimely” or

“unduly delayed.” 

2. Undue Prejudice

The second, and most important, factor in deciding a motion to amend the

pleadings, is whether the amendment would prejudice the nonmoving party. 

“Rule 15 . . . was designed to facilitate the amendment of pleadings except where

prejudice to the opposing party would result.” United States v. Hougham, 364

U.S. 310, 316 (1960). See also Evans v. McDonald’s Corp., 936 F.2d 1087,

1090–91 (10th Cir. 1991) (“As a general rule, a plaintiff should not be prevented

from pursuing a valid claim . . . , provided always that a late shift in the thrust of

the case will not prejudice the other party in maintaining his defense upon the

merits.” (internal quotation marks omitted)); Eastern Food Servs., Inc. v.

Pontifical Catholic Univ. Servs. Ass’n, 357 F.3d 1, 8 (1st Cir. 2004) (“Once the

adversary has answered, amendment is no longer allowed as of right, Fed. R. Civ.
-27-

P. 15(a), but in general permission is liberally granted where there is no

prejudice.”); 6 Wright, Miler & Kane, Federal Practice and Procedure § 1487

(2d ed. 1990) (“Perhaps the most important factor listed by the Court and the

most frequent reason for denying leave to amend is that the opposing party will be

prejudiced if the movant is permitted to alter his pleading.”). 

Courts typically find prejudice only when the amendment unfairly affects

the defendants “in terms of preparing their defense to the amendment.” Patton v.

Guyer, 443 F.2d 79, 86 (10th Cir. 1971). Most often, this occurs when the

amended claims arise out of a subject matter different from what was set forth in

the complaint and raise significant new factual issues. Compare Hom v. Squire,

81 F.3d 969, 973 (10th Cir. 1996) (finding prejudicial a motion “to add an

entirely new and different claim to [the plaintiff’s] suit little more than two

months before trial”), with Gillette v. Tansy, 17 F.3d 308, 313 (10th Cir. 1994)

(finding no evidence of prejudice when the “Petitioner’s [amended] claims track

the factual situations set forth in his [original] claims”), Childers v. Indep. Sch.

Dist. No. 1, 676 F.2d 1338, 1343 (10th Cir. 1982) (ruling that the district court’s

refusal to allow an amendment was “particularly egregious in this case because

the subject matter of the amendment was already alleged in the complaint”), and

R.E.B., Inc. v. Ralston Purina Co., 525 F.2d 749, 751–52 (10th Cir. 1975)

(finding no prejudice when “[t]he amendments did not propose substantially

different issues”). 
-28-

Prime Equipment repeatedly asserts that the addition of an alteration

product liability claim to the pleadings would result in “obvious” prejudice to it, 

but offers little explanation as to how it would be prejudiced in light of the

similarities between the complaint and the amended claim. The complaint

asserted a negligence claim against Prime Equipment for failing to “properly

inspect, repair and maintain the lift.” Complaint 1. The new claim against Prime

Equipment was for “materially alter[ing] the subject scissor lift by removal of the

[] solid guardrail safety feature.” Appellant’s App. 81. While the two claims are

different in form, there is a significant overlap in the factual underpinnings and

defenses. Both claims rely on the proposition that Mr. Minter was injured

because “the scissor lift as provided to [him] was in a condition with a detachable

chain link fitted in place of a solid steel guardrail[, which] . . . was contrary to

established safety standards.” Appellee’s Supp. App. 37–38. Moreover, most of

Prime Equipment’s defenses to the negligence claim apply with equal force to the

product liability claim, including its defenses that the lift was safe for its intended

use, that it did not violate the applicable ANSI or OSHA standards at the time of

manufacture, that it was not defective or unreasonably dangerous, and that Mr.

Minter’s actions were the sole cause of the accident. Prime Equipment’s only

defense to the negligence claim that it could not use against the product liability

claim is comparative negligence, which would include the marijuana evidence. 

Moreover, Prime Equipment defended against a retailer’s product liability claim
-29-

in the underlying state court action, and all of the discovery materials from that

case were available to Prime Equipment in its defense below. These

circumstances belie Prime Equipment’s argument that it was unprepared for Mr.

Minter’s late assertion of an alteration product liability claim. 

Prime Equipment’s claim of prejudice thus rests, in reality, on the viability

of two defenses it argues it would have prepared if it had known about the

alteration product liability claim at an earlier stage in the litigation. First, Prime

Equipment alleges that it would have conducted more discovery to determine who

was responsible for altering the lift. Second, it argues that it never would have

signed the Joint Stipulation, which helped to exonerate Economy from the product

liability claim, if it thought there was a product liability claim against it as well. 

Prime Equipment contends that it would have been prejudiced by the late

addition of an alteration product liability claim because “the evidence was

inconclusive as to who altered” the lift, and it would have “discovered this case

up differently” if it thought the case “was about alteration.” Appellee’s Br. 6–7,

12. The Plaintiff counters that “[t]he fact that ‘Prime [Equipment] removed the

bar’ is evident from the [Joint] Stipulation, and the Record,” Appellant’s Reply

Br. 2, since Prime Equipment stipulated that the “scissor lift was . . .

manufactured and sold by Economy Co. with a solid guardrail around the entire

upper perimeter of the scissor lift platform,” and that “[w]hen Prime Equipment

sold the scissor lift, the solid guardrail had been removed from the entry end and
Prime Equipment argues that the “[e]vidence indicated that it was not 8

Prime [Equipment] that altered the lift,” Appellee’s Br. 22, but the evidence it

refers to is the testimony of a witness who claimed that Economy altered the

lift—a position that Prime Equipment explicitly disavowed in the Joint

Stipulation. 

-30-

replaced with a [] chain entry.” Pretrial Order 8. Nonetheless, Prime Equipment

maintains that the lift may have been altered by someone else. During arguments

before the district court, Prime Equipment explained that Economy had “two

[sales] invoices on the same day; one [scissor lift] goes to [a company named]

Forte Rents up north someplace, and the other one goes to . . . Prime

[Equipment].” Appellee’s Br. 12. Prime Equipment speculates that Forte Rents

may have modified the guardrail system on the lift it bought from Economy, and

then sold that lift to Prime Equipment. 

Although an amendment may be prejudicial if its timing prevents the

defendant from pursuing a potentially promising line of defense, Prime

Equipment’s assertion that Forte Rents may have altered the lift and sold it to

Prime Equipment is far too speculative to support such a finding. Prime

Equipment does not cite any evidence indicating that it purchased the lift from

Forte Rents. In fact, before Prime Equipment entered into the Joint Stipulation, 8

it argued that it purchased the lift from Economy with a chainlink entry; and at

trial one of Prime Equipment’s employees testified that the company bought the

lift “brand new” from Economy, and that “Prime [Equipment] did not buy used
Although Prime Equipment might wish to implead the upstream 9

distributor, the fact that it could not do so in this action does not constitute

prejudice. If Prime Equipment were to be found liable under an alteration product

(continued...)

-31-

equipment for rental.” Appellee’s Supp. App. 81; Appellant’s App. 311. 

Moreover, if there was any evidence that Forte Rents was responsible for the

alteration, it should have surfaced during the underlying state court action, where

Prime Equipment was defending against a retailer product liability claim and

could have impleaded any upstream distributor. Prime Equipment had incentive

and opportunity to conduct discovery on this issue during the underlying state

court litigation, from which most of the discovery in this case was gathered, and

we therefore find no support for its claim of prejudice. 

More importantly, however, Prime Equipment’s claim of prejudice fails

because its attempt to pin responsibility for the alteration on an upstream

distributor is not a defense to an alteration product liability claim. Even if Prime

Equipment could produce evidence to support its theory that Forte Rents altered

the lift, “[i]n a strict liability action it is immaterial to the plaintiff’s case that the

defect in the product was not caused by the distributor.” Braden v. Hendricks,

695 P.2d 1343, 1350 (Okla. 1985). Under Oklahoma law, it is enough that Prime

Equipment admits to selling the lift in its altered condition. Id. Consequently,

there is no merit to Prime Equipment’s claim that the amendment is prejudicial

because it was prevented from arguing that Forte Rents altered the lift. 

9
(...continued) 9

liability theory, and after the judgment it discovered evidence establishing that

Forte Rents altered the lift, Prime Equipment could file a separate action for

indemnity against Forte Rents as an upstream distributor. See Fed. R. Civ. P.

14(a); Okla. Stat. tit. 12 § 2014; State Farm Mut. Auto. Ins. Co. v. Perry, 104

P.3d 1136, 1138–39 & n.3 (Okla. Civ. App. 2004).

-32-

Prime Equipment’s second claim of prejudice arises out of the Joint

Stipulation. During the underlying state court action, where the plaintiff asserted

negligence and product liability claims against both defendants, Prime Equipment

filed a cross-claim against Economy for indemnity from the plaintiff’s

manufacturer product liability claim. The Joint Stipulation prevented Prime

Equipment from filing a similar motion in the federal case, and Prime Equipment

argues that it “never would have made such a stipulation had there been an

alteration product liability claim against it.” Appellee’s Br. 7. The district court

agreed with Prime Equipment, concluding that the “somewhat curious” Joint

Stipulation was consistent with Prime Equipment’s position that “it believed that

a products liability claim had not been stated against it.” Order 6. 

We believe that concerns about prejudice run the other way. It is true, as

the district court observed, that the strategy behind the Joint Stipulation is

“somewhat curious.” But one thing is clear: the defendants’ change in position

potentially undermined the plaintiff’s entire products liability case. During the

first five years of the litigation, when the complaint was formulated and until

after completion of discovery, Prime Equipment maintained and presented
-33-

evidence that the chainlink closure had been installed on the lift before it came

into Prime Equipment’s possession. Plaintiff crafted his case accordingly, suing

Economy for defective design and manufacture, and Prime Equipment for

negligent maintenance and repair. The revelation of June 12, 2003 changed all of

that. Prime Equipment entered a Joint Stipulation and submitted evidence that at

the time the lift was sold by Economy, it was equipped with a solid metal

guardrail. At the same time, Prime Equipment filed an evidentiary motion

limiting the plaintiff to “a negligence theory only.” Appellee’s Supp. App. 10. 

Unless his complaint were construed to include a products liability claim against

Prime Equipment or he were permitted to amend, Mr. Minter would be left with

no products liability claim at all. If Prime Equipment could absolve Economy of

responsibility for the defect, and simultaneously avoid liability by holding the

plaintiff to a narrow construction of the complaint, this would mean that no one

could be held responsible for the alleged defect. We do not think it is

“prejudicial” to Prime Equipment not to allow this gambit to succeed. On the

contrary, allowing Mr. Minter to assert an alteration product liability claim

against Prime Equipment is necessary so that he is not prejudiced by Prime

Equipment’s extraordinary change in its account of what happened. 

Due to the rather unusual circumstances surrounding the Joint Stipulation

and Prime Equipment’s objection to the pretrial order, we agree with the plaintiff

that the district court’s finding of prejudice was a clear error. “The Federal Rules
-34-

of Civil Procedure are designed to put an end to the ‘sporting theory of justice,’

by which the result depends on . . . the skill and strategy of counsel.” Mid-West

Paper Prods. Co. v. Cont’l Group, Inc., 596 F.2d 573, 579 (3d Cir. 1979)

(internal quotation marks omitted). See United States ex rel. Precision Co. v.

Koch Indus., Inc., 31 F.3d 1015, 1018 (10th Cir. 1994) (“The Federal Rules . . .

accept the principle that the purpose of pleading is to facilitate a proper decision

on the merits.” (internal quotation marks omitted)); 6 Wright, Miller & Kane,

Fed. Prac. & Proc. 3d § 1488 (2d ed. 1990). Although Prime Equipment gave up

the ability to file a cross-claim against Economy when it entered into the Joint

Stipulation, it did so as part of a strategy designed to avoid a decision on the

merits of Mr. Minter’s product liability claim. Prime Equipment cannot now

argue that the amendment to add an alteration product liability claim against it is

prejudicial because of the Joint Stipulation. Whatever harm befalls Prime

Equipment as a result of entering into the Joint Stipulation is of its own making,

and therefore does not qualify as prejudice under Rule 15(a). 

B. Evidentiary Rulings

Mr. Minter argues that the jury verdict in favor of Prime Equipment on the

failure to warn claim must be vacated because of two allegedly erroneous

evidentiary rulings in the proceedings below. The first alleged error is the district

court’s decision to exclude the evidence of Prime Equipment’s repair work on the

scissor lift after Mr. Minter’s accident. The second is the district court’s decision
-35-

to admit evidence that Mr. Minter was not wearing a safety belt or hard hat on the

day of his injury. We review the district court’s evidentiary rulings for an abuse

of discretion, United States v. Apperson, 441 F.3d 1162, 1198 (10th Cir. 2006),

and affirm. 

1. Subsequent Remedial Measure

Federal Rule of Evidence 407 provides: 

When, after an injury or harm allegedly caused by an event, measures

are taken that, if taken previously, would have made the injury or

harm less likely to occur, evidence of subsequent measures is not

admissible to prove negligence, culpable conduct, a defect in a

product, a defect in a product’s design, or a need for a warning or

instruction. This rule does not require the exclusion of evidence of

subsequent measures when offered for another purpose, such as

proving ownership, control, or feasibility of precautionary measures,

if controverted, or impeachment.

Rule 407 “codifie[s] the generally accepted common law rule which excluded

remedial measures which were taken after an accident.” Rimkus v. Northwest

Colo. Ski Corp., 706 F.2d 1060, 1064 (10th Cir. 1983). The Advisory Committee

articulated two rationales for Rule 407. First, it observed that subsequent

remedial measures often are “not in fact an admission, since the conduct is

equally consistent with injury by mere accident or through contributory

negligence.” Fed. R. Evid. 407 advisory committee’s note. Second, it found that

there is an important “social policy of encouraging people to take, or at least not

discouraging them from taking, steps in furtherance of added safety.” Id.; see

also Rimkus, 706 F.2d at 1064. The application of Rule 407 in any particular case
-36-

must be guided by these two considerations. See Kelly v. Crown Equip. Co., 970

F.2d 1273, 1276 (3d Cir. 1992). 

More than a year after Mr. Minter’s accident, Prime Equipment was hired

to perform the annual safety inspection on the scissor lift. It made a number of

repairs while it had possession of the lift. One of those was to replace the

chainlink entry with a solid metal guardrail. In the proceedings below, the

plaintiff sought to introduce evidence of Prime Equipment’s repair work on the

scissor lift. Before the start of trial, Prime Equipment filed a motion in limine to

exclude the evidence of this repair work pursuant to Rule 407. The district court

granted Prime Equipment’s motion, concluding that “the addition of the metal rod

represents a subsequent remedial measure.” Order, Nov. 24, 2003, at 4–5. On

appeal, the plaintiff offers two reasons why the district court’s ruling was

erroneous. 

The plaintiff first contends that Prime Equipment should be estopped from

arguing that the installation of a solid guardrail constitutes a “remedial measure”

because at trial it took the position that a chainlink entry is just as safe as a bar. 

Rule 407 defines a remedial measure as one that, “if taken previously, would have

made the injury or harm less likely to occur.” Fed. R. Evid. 407. If Prime

Equipment had, as the plaintiff contends, “submitted evidence that the [solid

guardrail] would not have made the event less likely to occur because the chain

was just as safe and effective as the bar,” Appellant’s Br. 33, then this Court
-37-

would have to address the legal underpinnings of this estoppel claim. Yet Prime

Equipment never argued that a chainlink entry is just as safe as a solid guardrail. 

It argued that a “properly used” chainlink entry is just as safe as a solid guardrail,

and that Mr. Minter caused his own accident by failing to close the chainlink

entry before operating the scissor lift. Prime Equipment does not dispute Mr.

Minter’s claim that a solid guardrail would have helped prevent his fall. Under

Rule 407, therefore, Prime Equipment’s act of replacing the chainlink entry with a

solid guardrail is undoubtedly a subsequent remedial measure. 

Mr. Minter’s second argument is that the evidence of Prime Equipment’s

subsequent repair work on the lift should have been admitted at trial to rebut the

testimony of one of Prime Equipment’s witnesses. Rule 407 states that it “does

not require the exclusion of evidence of subsequent measures when offered for

another purpose, such as . . . impeachment.” Fed. R. Evid. 407. The

impeachment exception to Rule 407 is necessary to prevent litigants from taking

“unfair advantage” of the Rule by adopting a position at trial that is inconsistent

with their previous decision to take remedial measures after the accident. Wood

v. Morbark Indus., Inc., 70 F.3d 1201, 1208 (11th Cir. 1995) (evidence of

subsequent modifications can be introduced to rebut testimony that “left the jury

with the impression that [the defendant] had made no modifications to the

[product]”); see also In re Air Crash Disaster, 86 F.3d 498, 531 (6th Cir. 1996)

(evidence of subsequent design changes to correct deficiencies is admissible to
-38-

rebut a witness’s claim that the product was “state of the art”); Polythane Sys.,

Inc. v. Marina Ventures Int’l., LTD., 993 F.2d 1201, 1210–11 (5th Cir. 1993)

(evidence of subsequent modifications is admissible to impeach testimony that the

product was “one of the strongest in the world”). 

The impeachment exception, however, must be read narrowly, lest it

swallow the rule. Applied loosely, “any evidence of subsequent remedial

measures might be thought to contradict and so in a sense impeach [a party’s]

testimony.” Complaint of Consolidated Coal Co., 123 F.3d 126, 136 (3d Cir.

1997) (emphasis and internal quotation marks omitted). As the Seventh Circuit

explained in Probus v. K-Mart, Inc., 794 F.2d 1207 (7th Cir. 1986): 

It is undoubtedly true that evidence of subsequent remedial measures

can be said to contradict, and hence, in a sense, ‘impeach’ a

defendant’s contention that he was exercising due care or that

materials used in the manufacture of a product were appropriate for

their intended application. Yet allowing that and no more to satisfy

the impeachment exception would elevate it to the rule.

 

Id. at 1210. Consequently, the impeachment exception has been confined to

evidence of subsequent remedial measures that is “necessary to prevent the jury

from being misled.” Wood, 70 F.3d at 1208; see also Complaint of Consolidated

Coal Co., 123 F.3d at 136 (“[T]he evidence offered for impeachment must

contradict the witness’s testimony directly.”); Harrison v. Sears, Roebuck & Co.,

981 F.2d 25, 31 (1st Cir. 1992) (noting that the impeachment exception requires
-39-

“a great[] nexus between the statement sought to be impeached and the remedial

measure”). 

According to the plaintiff, the evidence of Prime Equipment’s subsequent

remedial measures should have been admitted at trial to rebut the testimony from

Prime Equipment’s expert witness that the chainlink entry was “basically

equivalent” to a solid guardrail. Appellant’s App. 493–94. Yet this testimony is

not directly contradicted by the evidence of Prime Equipment’s decision to install

a solid guardrail on the lift. The witness testified that a chainlink entry is

“basically equivalent” to a solid guardrail “as long as [it is] in place,” and that the

chainlink entry was not unreasonably dangerous because “if [it] would have been

properly latched, [Mr. Minter] would not have fallen out of the scissor lift and

been injured.” Id. at 493–95. This testimony is consistent with the evidence at

trial that the ANSI safety standards were changed in 1991 to require solid

guardrails in response to reports of workers operating the lift without latching the

chainlink entry. Moreover, Prime Equipment did not dispute that a solid guardrail

reduces the danger of falls for lift operators who might otherwise forget to latch

the chainlink entry or fail to do so properly. Consequently, the evidence of Prime

Equipment’s subsequent repair work on the guardrail does not fall within the

impeachment exception to Rule 407. 
-40-

2. The Safety Belt and Hard Hat Evidence

Mr. Minter’s last argument on appeal is that the district court wrongfully

denied his motion in limine regarding the evidence that he was not wearing a

safety belt or hard hat at the time of the accident. Both types of safety equipment

were available to Mr. Minter on the day of the incident, and the district court

concluded that the safety belt and hard hat evidence “is admissible to show

Plaintiff’s conduct in the workplace. The resulting effect from the failure to

employ these safety devices is a matter for the jury to consider in their

deliberations.” Order, Nov. 24, 2003, at 3. Consequently, Prime Equipment was

allowed to argue at trial that “a safety belt would have prevented [Mr. Minter]

from falling out of the lift had he been wearing it,” Appellant’s App. 495, and to

introduce the portions of Mr. Minter’s deposition testimony where he admitted

that a hard hat “might have saved [his] head from hurting.” Appellee’s Supp.

App. 29. On appeal, the plaintiff contends that the safety belt and hard hat

evidence was relevant only to a comparative negligence defense, and since he

voluntarily dismissed his negligence claims against Prime Equipment before trial,

the evidence should have been excluded. Prime Equipment defends the admission

of the safety belt and hard hat evidence on the ground that it was relevant to the

issues of causation and mitigation of damages, and was therefore properly

admitted at trial. 
-41-

We affirm the district court’s ruling on the narrow ground that the safety

belt and hard hat evidence was relevant to the specific causation issues raised by

Mr. Minter’s failure to warn claim. Oklahoma law requires the plaintiff, in a

failure to warn lawsuit, to “establish that the failure to warn was a proximate,

producing cause of the injuries received.” Duane v. Okla. Gas & Elec. Co., 833

P.2d 284, 286 (Okla. 1992). Mr. Minter therefore had to show that if Prime

Equipment had posted an adequate warning on the lift, he would have heeded it. 

See, e.g., Daniel v. Ben E. Keith Co., 97 F.3d 1329, 1333 (10th Cir. 1996). 

Although there is a presumption under Oklahoma law that the plaintiff would

have read and heeded an adequate warning, the defendant may rebut that

presumption by showing that the warning would not have altered the plaintiff’s

behavior. Id. at 1332. Prime Equipment argues that Mr. Minter’s failure to wear

a safety belt or hard hat on the day of the accident demonstrates his “propensity

for recklessness.” Appellee’s Br. 35. While Prime Equipment may be overstating

its case, we find that the safety belt and hard hat evidence bears sufficient relation

to the question of whether Mr. Minter would have heeded an adequate warning

that Prime Equipment was entitled to present the safety belt and hard hat evidence

to the jury. Cf. Daniel, 97 F.3d at 1333.

III. CONCLUSION

The order of the district court striking from the pretrial order Mr. Minter’s

product liability claim against Prime Equipment stemming from the alteration of
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the scissor lift is therefore REVERSED, and the case is REMANDED to the

district court for further proceedings. The evidentiary rulings of the district court

related to the failure to warn claim are upheld, and the jury verdict on that claim

is AFFIRMED.