The Appellate Blog



Prevailing Factor Clarified For Workers' Heart Attack Cases

Posted January 19, 2018

For a quarter century, Ulysses White worked as a machinist at ConAgra in Marshall, Missouri. It was over 100 degrees at work the day he died. Colleagues found him collapsed on the floor just before lunchtime. An autopsy found his cause of death to be “cardiac arrhythmia resulting from severe coronary artery disease.”

In White v. Conagra Packaged Foods, LLC, No. SC96041 (Dec. 19, 2017), the White family sought workers compensation benefits. They argued that extreme heat and working conditions that day caused White’s death. ConAgra countered that his death was simply the unfortunate result of his underlying heart disease.


To obtain workers compensation benefits after a cardiovascular event, a claimant must show under Section 287.020.3(4) there was an accident (a trauma) that was the prevailing factor in the injury. Of course, claimants must also show that the accident occurred in the course of employment under Section 287.120.1. As you might guess, the main rub in White’s case was the prevailing factor question. Each side had their own expert to tell their story of causation. Ultimately, the administrative law judge (workers comp cases are decided administratively in the first instance) found ConAgra’s evidence more persuasive on that issue and denied the White family's claim. The Labor and Industrial Relations Commission affirmed that finding on appeal.

By the time the case got to the Supreme Court, the framework for the analysis was jumbled. Appellants were arguing that the Commission erred by holding them to a “prevailing factor” burden of proof under Section 287.020 rather than the preponderance of the evidence standard that is necessary to show that White’s accident arose out of his employment. But that issue needn’t be addressed, the Court said, because another element of the claimant’s case was dispositive. At bottom, the claim foundered on unpersuasive expert testimony about the cause of White’s heart attack.

Practice Tip: The Opinion hints at some confusion between the burden of proof and the standard of proof. This is a common misstep. And it’s understandable. After all, the “burden of proof” itself actually refers to two different concepts: the burden of production and burden of persuasion. But that’s a discussion for another post.

As this case illustrates, the burden of proof is distinct from the standard of proof. Here, the statute required White’s family to prove as an element of the claim that the working conditions were the prevailing cause of his heart attack. This element was part of their burden of proof. This is no different from, say, a breach of contract case, where the burden of proof includes proving the element of breach. But this burden does not alter the basic standard of proof. That is, the claimant had to convince the ALJ and Commission (the fact finders) by a preponderance of the evidence that White’s working conditions were the prevailing factor of his heart attack.