Opinion ID: 1528539
Heading Depth: 1
Heading Rank: 3

Heading: Proximate Cause Standard Substantial Factor or But For Workers' Compensation Determinations

Text: In the context of addressing Delaware's new contributory negligence statute in a tort case, this Court noted that the but for test and the substantial factor test are two different standards for determining proximate cause. Culver v. Bennett, Del.Supr., 588 A.2d 1094, 1097 (1991) (citing W. Keeton, Prosser and Keeton on the Law of Torts 266 (5th ed.1984)). Prosser and Keeton have summarized the but for or sine qua non rule as: The defendant's conduct is a cause of the event if the event would not have occurred but for that conduct; conversely, the defendant's conduct is not a cause of the event, if the event would have occurred without it. Prosser and Keeton on Torts 266. Prosser and Keeton have summarized the substantial factor rule as: the defendant's conduct is a cause of the event if it was a material element and a substantial factor in bringing it about. Id. at 267. In Culver, this Court held that in Delaware tort cases, proximate cause must be determined exclusively by an application of the but for standard. Culver v. Bennett, 588 A.2d at 1099. Similarly, in Reese v. Home Budget Center , in the context of a specific and identifiable industrial accident, this Court held that the `but for' definition of proximate cause in the substantive law of torts finds equal application in fixing the relationship between an acknowledged industrial accident and its aftermath. Reese v. Home Budget Center, Del.Supr., 619 A.2d 907, 910 (1992). In Reese, we explained If the worker had a preexisting disposition to a certain physical or emotional injury which had not manifested itself prior to the time of the accident, an injury attributable to the accident is compensable if the injury would not have occurred but for the accident. The accident need not be the sole cause or even a substantial cause of the injury. If the accident provides the setting or trigger, causation is satisfied for purposes of compensability. 619 A.2d at 910. We reaffirm that holding in Reese: when there is an identifiable industrial accident, the compensability of any resultant injury must be determined exclusively by an application of the but for standard of proximate cause. Id. In cases where a claimant is injured by the aggravation of a pre-existing condition and there is no identifiable industrial accident, however, causation is governed by the usual exertion rule. Duvall v. Charles Connell Roofing, Del.Supr., 564 A.2d 1132, 1136 (1989). [2] The usual exertion rule provides that the injury is compensable, notwithstanding the previous condition, if the ordinary stress and strain of employment is a substantial factor in causing the injury. Id. In Reese, this Court explained that the substantial factor standard of proximate cause was adopted in Duvall because of the difficulty of identifying a specific link between regular job-related duties and the aggravation of preexisting ailments. Reese v. Home Budget Center , 619 A.2d at 911. A similar difficulty was also recognized by this Court when a claimant seeks workers' compensation for a mental injury that was not the result of a specific trauma but rather was due to gradual and ordinary job-related stress. See State v. Cephas, Del. Supr., 637 A.2d 20 (1994). In Cephas, this Court reaffirmed the distinction between the factual predicate for determining compensability pursuant to either the but for standard of proximate cause, as explained in the Reese holding, or the substantial factor standard of proximate cause, as adopted in the Duvall holding. Id. at 27-28. An injured claimant can recover workers' compensation benefits when there is no specifically identifiable physical industrial accident, as long as the ordinary stress and strain of employment is a substantial factor in proximately causing the injury. State v. Cephas, 637 A.2d at 27. Accord Reese v. Home Budget Center, Del.Supr., 619 A.2d 907, 911 (1992); Duvall v. Charles Connell Roofing, Del.Supr., 564 A.2d 1132, 1136 (1989). See also Page v. Hercules, Del.Supr., 637 A.2d 29, 33 (1994).