The primary issue we face in this appeal is whether an injured worker presented a viable cause of action against his employer’s workers’ compensation carrier for bad faith in denying his claim for workers’ compensation benefits. The district court granted the carrier’s motion for summary judgment and the court of appeals affirmed the decision. On further review, we vacate the decision of the court of appeals, affirm the decision of the district court in part and reverse in part, and remand for further proceedings.
I. Background Facts and Proceedings.
David Mcllravy was employed by Ace Construction Company as an iron worker. His work commonly required him to bend, lift, stoop, carry, and climb. He normally wore a tool belt that weighed approximately twenty pounds.
On August 7, 1997, Mcllravy injured his right knee while working at a job site in Ames. Mcllravy was helping erect a building at the time. The injury occurred after Mcllravy descended from a ladder and was walking across a level cement floor to pick up some items some distance away. While walking, he felt and heard a pop in his knee. He was not wearing his tool belt at the time, and was not carrying anything. He had experienced no prior problems with his knee. Mcllravy felt no pain at the time and completed his work tasks for the day. That evening, however, after returning home, his knee began to swell. It was extremely sore and stiff the following morning. Mcllravy went to the work site in the morning, but the condition of his knee prevented him from working after a short period of time. His employer directed him to a medical clinic in West Des Moines, where he was referred to Jon C. Gehrke, M.D., an orthopedic surgeon.
On August 12, 1997, a claims examiner employed by the workers’ compensation carrier for Ace Construction, North River Insurance Company/Crum & Forster Insurance Company, interviewed Mcllravy for the purpose of determining whether to pay benefits for the injury. On August 18 the claims examiner sent Mcllravy a letter advising him that benefits were denied. The letter explained that the knee injury was idiopathic and only coincidentally occurred during working hours.
On August 25, 1997, Dr. Gehrke sent a letter to the claims examiner indicating he performed an MRI on Mcllravy’s right knee. The procedure revealed the injury was a torn medial meniscus. He further *327 expressed his opinion, without explanation, that the injury was “work-related.” After conservative treatment failed, Dr. Gehrke performed partial medial menisectomy surgery to repair the knee. North River made no effort to obtain an independent medical examination to dispute or corroborate Dr. Gehrke’s opinion on the cause of the injury. The company also did not consult an attorney to determine whether Dr. Gehrke’s letter had any impact on the denial of Mcllravy’s claim.
North River continued to deny benefits and Mellravy filed a contested case proceeding with a demand for penalty benefits. The parties deposed Dr. Gehrke in February 1998, who explained he believed the injury sustained by Mellravy was work-related because Mellravy was working when the injury occurred and his job involved heavy labor activities, which placed him at greater risk for such injuries than workers engaged in less labor intensive activities. North River did not obtain a medical expert to review Dr. Gehrke’s opinion following the deposition, and conducted no further investigation.
The industrial commissioner awarded benefits to Mellravy, and assessed a penalty for the unreasonable denial of benefits. The district court affirmed the decision of the industrial commissioner on its review of the case, and our court of appeals affirmed the decision of the district court on appeal.
On August 3, 1999, Mellravy filed a tort action against North River for bad faith refusal to pay the workers’ compensation benefits. North River moved for summary judgment, and Mellravy moved for partial summary judgment. North River argued that Mcllravy’s action was required to be dismissed because the workers’ compensation claim was fairly debatable as a matter of law. Mellravy argued that the element of the bad faith tort requiring him to establish the absence of a reasonable basis for denying benefits was established as a matter of law under the doctrine of issue preclusion when the industrial commissioner awarded penalty benefits as a part of its decision to award workers’ compensation benefits.
The district court denied Mcllravy’s motion for a partial summary judgment and granted summary judgment for North River. It found that the doctrine of issue preclusion was inapplicable to the case, and further found there was no substantial evidence presented to establish the absence of a reasonable basis by North River for denying benefits. The district court found the claim for benefits was fairly debatable at the time of denial because the cause of injury was idiopathic. The court of appeals affirmed. It found there was a reasonable debate whether the injury was caused by Mcllravy’s individual susceptibility to the injury or the heavy labor activities associated with his job because Mellravy was not engaged in any work activity that placed stress or trauma on his knee at the time of the injury.
II. Scope of Review.
We review a ruling on a summary judgment motion for errors at law.
Harvey v. Care Initiatives, Inc.,
In ruling on a summary judgment motion, the facts must be viewed in a light most favorable to the party resisting the motion.
McNally & Nimergood v. Neumann-Kiewit Constructors, Inc.,
III. Applicability of Issue Preclusion.
Mellravy argues that the element of the bad faith tort requiring him to establish the absence of a reasonable basis for denying benefits was established as a matter of law under the doctrine of issue preclusion when the industrial commissioner awarded penalty benefits as a part of its decision to award workers’ compensation benefits. In so arguing, Mellravy seeks to intermingle two distinct methods by which a self-insured employer or an employer’s workers’ compensation carrier may be penalized due to their delay in payment of workers’ compensation benefits.
The first method is described by statute. It arises from the language of Iowa Code section 86.13, which states in part:
If a delay in commencement or termination of benefits occurs without reasonable or probable cause or excuse, the workers’ compensation commissioner shall award benefits in addition to those benefits payable under this chapter, or chapter 85, 85A, or 85B, up to fifty percent of the amount of benefits that were unreasonably delayed or denied.
Iowa Code § 86.13 (1999) (emphasis added).
The determination of whether a delay “occurs without reasonable or probable cause or excuse,” requires an examination of the employer’s or the carrier’s actions in response to the employee’s claim.
Id.
A delay in commencement of benefits is permissible if “(1) the delay was necessary for the insurer to investigate the claim or (2) the employer had a
reasonable basis
to contest the employee’s entitlement to benefits.”
Christensen v. Snap-On Tools Corp.,
The second method by which a self-insured employer or employer’s workers’ compensation carrier may be penalized for a delay in payment of benefits is
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by a private cause of action for first-party bad faith.
2
This cause of action arises from “ ‘the knowing failure to exercise an honest and informed judgment’” on the part of a defendant from whom the employee seeks compensation due to work-related injuries.
Kiner v. Reliance Ins. Co.,
Given the use of the phrase “reasonable basis” in the standard for imposition of the statutory penalty and in the standard for imposition of a civil penalty, it is understandable that Mcllravy would utilize the potential preclusive effect one reasonable basis determination would have on the other reasonable basis determination in either of the particular contexts in which the standards apply. In fact, Mcllravy offers at least one recent case in support of his argument that issue preclusion applies in this case.
See Gibson v. ITT Hartford Ins. Co.,
Moreover, there are a number of differences between the statutory and common law provisions under which-Mcll-ravy has sought redress. The most significant for this case is the difference in burdens of proof placed on the parties in the two different proceedings. In the administrative context, where the industrial
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commissioner is responsible for applying the provisions of section 86.13, the defendant/employer or carrier bears the burden of proving that its denial of benefits had a reasonable basis.
Christensen,
The primary purpose of issue preclusion is to protect litigants from the “vexation of relitigating identical issues with identical parties or those persons with a sufficient connective interest to the prior litigation” with an additional benefit of promoting judicial economy.
State ex rel. Casas v. Fellmer,
Although an issue is actually litigated and determined by a valid and final judgment, and the determination is essential to the judgment, relitigation of the issue in a subsequent action between the parties is not precluded in the following circumstances: ...
(4) The party against whom preclusion is sought had a significantly heavier burden of persuasion with respect to the issue in the initial action than in the subsequent action; the burden has shifted to his adversary; or the adversary has a significantly heavier burden than he had in the first action.
Heidemann v. Sweitzer,
In this case, the burden has shifted between the two parties. In the administrative procedure, the burden was on North River. In this civil suit, Mcllravy has the burden. Given the different burdens of proof between the two different penalty mechanisms and the two different stages of the North River/Mcllravy dispute, issue preclusion is inapplicable in this case. The district court was correct in overruling Mcllravy’s motion for partial summary judgment on this issue.
IV. Propriety of Summary Judgment.
The second issue we face in this appeal is whether the district court properly granted summary judgment in favor of North River based on the court’s finding that Mcllravy failed to present substantial evidence- to establish the absence of a reasonable basis by North River for denying ' benefits. In
Thompson v. United States Fidelity & Guaranty Co.,
there are no unique rules that apply when a district court rules on a directed-verdict motion in a bad-faith case. In such a case, as in all others,
[t]ime-honored rules govern our review of [a court’s ruling on] such motions. The primary standard is that of substantial evidence; where no substantial evidence exists to support each element of a plaintiffs claim, directed verdict or judgment n.o.v. is proper. Substantial evidence is that which a “reasonable mind would accept as adequate to reach a conclusion.” Where reasonable minds could differ on an issue, directed verdict is improper and the case must go to the jury-
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Thompson,
a court should direct a verdict for the defendant only when, viewing the record in the light most favorable to the claimant, there is no substantial evidence to support the elements of the claim, ie., that the insurer lacked a reasonable basis for denial and that it knew or should have known it lacked such a basis.
Thompson,
A key dispute in this case focuses on the point in time at which a court should look to determine the reasonableness of an insurer’s actions in denying benefits in light of the evidence in its possession. Mcllra-vy asserts that North River’s obligation to act reasonably was present throughout all stages of their dispute, including the point in time after North River’s first denial of benefits when it received the letter from Dr. Gehrke opining that Mcllravy’s injury was work-related. North River argues that it had a reasonable basis in denying benefits initially and need not reestablish such a basis at subsequent points in time, particularly if such a reassessment was supported by the opinion of a doctor with no training in making determinations of legal causation. We have previously indicated that in cases of this type the inquiry must focus on the defendant’s initial denial as well as “whether, at some later date, [the insurer] became aware there was no reasonable basis to continue denying plaintiffs’ claim.”
Dirks v. Farm Bureau Mut. Ins. Co.,
We conclude the information gathered from the initial interview of Mcll-ravy gave North River a reasonable basis to deny the claim. An injury must arise out of the worker’s employment to be com-pensable. This means “‘the injury must not have coincidentally occurred while at work, but must in some way be caused by or related to the working environment or the conditions of ... employment.’ ”
Floyd v. Quaker Oats,
In this case, on the date North River wrote the letter denying the claim, it knew Mcllravy was simply walking at the time of injury, with no additional facts to indi *332 cate the work environment or conditions of work contributed in any way to the injury. Although Mcllravy was engaged in a work activity, there was nothing to suggest that something about the work environment or condition of work contributed to the injury. Thus, the question is whether North River later became aware there was no reasonable basis to continue to deny the claim.
The evidence submitted at the summary judgment proceeding showed North River received the letter from Mcllravy’s treating physician six days after it denied the claim. This letter expressed a clear opinion that the injury was work-related, but provided no further explanation. The entire relevant portion of the five-sentence letter stated:
On August 7, 1997, he injured his right knee while at work. An MRI was obtained, revealing a large medial meniscus tear — this is definitely a work-related injury.
Although the opinion was expressed by Dr. Gehrke with a high degree of certainty, the letter did not include any reasons, medical or otherwise, to support the opinion. Other than the unsupported opinion of the doctor, North River had no additional facts or information to reevaluate its earlier response that the injury was not work-related.
However, North River later received additional information explaining Dr. Gehrke’s opinion. This information was obtained during the course of his deposition in February 1998. Dr. Gehrke explained that the injury was work-related because Mcllravy was at work, his profession involved heavy lifting activities, and the nature of his profession placed him at greater risk for knee injuries than other professions. The new information North River received from this deposition was that Mcllravy was at greater risk of sustaining a knee injury than workers in less labor-intensive professions. This was evidence that the injury sustained by Mcllravy was related to “ ‘the working environment or the conditions of ... employment.’”
3
Floyd,
Notwithstanding this new evidence, North River continued to deny the claim. Moreover, it failed to present evidence in the course of the summary judgment proceeding to show that it conducted a further investigation in response to the new evidence. It failed to respond to this new evidence by investigating whether iron workers are more susceptible to knee inju *333 ries and failed to seek another medical opinion to refute or confirm Dr. Gehrke.
Although the new information provided in the deposition did not necessarily render the compensability issue undebatable, it did transform the reasonableness of the continued denial by North River into a jury question.
4
The reasonableness of the denial of a workers’ compensation claim by an insurer is a question of law only when the evidence is undisputed and only one inference can be drawn from the evidence. The facts of this case were undisputed, but the inferences were not. Bad faith may be inferred from a flawed investigation, and the facts of this case place the adequacy of the investigation conducted by North River after the deposition of Dr. Gehrke into question.
See Reuter v. State Farm Mut. Auto. Ins. Co.,
V. Conclusion.
We conclude the district court properly overruled Mcllravy’s motion for partial summary judgment on issue preclusion *334 based on its finding that the issue of North River’s reasonable basis for denying Mell-ravy workers’ compensation benefits was not precluded by the reasonable basis determination made through the course of prior proceedings in this dispute. However, we find Mcllravy presented substantial evidence that North River did not have a reasonable basis for its denial of his workers’ compensation benefits after the deposition was taken. We conclude that the district court erred by granting North River’s motion for summary judgment on the reasonable basis determination.
DECISION OF COURT OF APPEALS VACATED; DISTRICT COURT JUDGMENT AFFIRMED IN PART, REVERSED IN PART, AND REMANDED.
Notes
. At first blush, a cause of action for bad faith pursued by an employee against an employer's workers’ compensation carrier appears to be a matter of "third-party” bad faith more than one of "first-party” bad faith.
See Long v. McAllister,
. We emphasize that the burden is on a claimant to prove both that an injury "arose out of" and "in the course of” employment.
Koehler Elec. v. Wills,
. North River rejected the medical opinion of the treating physician without explanation, and continued to rely upon its fact-based position that the injury only coincidentally occurred to Mcllravy while he was at work. However, North River had no medical evidence to support this position, and had knowledge that the only medical evidence in the case rejected the position.
In
Gilbert v. USF Holland, Inc.,
In this case, the facts concerning how the injury occurred are not in dispute, nor is the medical evidence of causation. While the facts alone do not disclose whether the injury arose out of employment, the additional medical evidence does not support causation. Medical evidence need not be accepted, but it can only be rejected based on valid specific reasons.
See Catalfo v. Firestone Tire & Rubber Co.,
