In May 2025, the Supreme Court of Washington overruled previous precedent regarding the deliberate intent to injure exception related to workers’ compensation immunity for employers, finding that an employee may sue its employer for latent disease injury if they can establish the employer had actual knowledge that latent diseases are “virtually certain” to occur. Cockrum v.
C.H. Murphy/Clark-Ullman, Inc., 569 P.3d 287, 289 (Wash. 2025). In Cockrum, the Plaintiff is a living mesothelioma claimant (“Plaintiff”), who filed suit against his employer as a premises defendant (“Defendant”), alleging that they deliberately intended to injure him by exposing him to asbestos without proper warnings or protections while he worked as a laborer at their facility from 1967 to 1997. He further argued that Defendant had actual knowledge that injury was certain to occur from asbestos exposure but willfully disregarded that knowledge by continuously exposing him to asbestos without proper warning or protection. Specifically, he alleged exposure to asbestos while working in the environmental lab, where he tested samples for asbestos without any protective gear.

Plaintiff was diagnosed with mesothelioma in March 2022. Notably, Plaintiff’s doctors referenced his history of occupational exposures to asbestos as part of his diagnosis. Plaintiff’s medical expert opined his mesothelioma was caused by his cumulative exposures to asbestos and explained that latent diseases ‘do not result in immediate apparent injury upon exposure but instead do not manifest until sufficient time has lapsed.’ Plaintiff’s medical expert testified that asbestos-related disease “is never certain to result from asbestos exposure or even from developing pleural plaques” and he was “not aware of any carcinogen for which exposure at a particular dose is medically certain to cause cancer in everyone.”

The Superior Court granted Defendant’s motion for summary judgment on the grounds that employers are immune from suit if they do not have actual knowledge that injury was certain to occur.  Defendant argued that Plaintiff could not satisfy the deliberate injury exception under the Industrial Insurance Act (“IIA”). The IIA provides that workers and their families or dependents are entitled to compensation for injuries sustained at work, regardless of employer fault, and employers are immune from lawsuits arising from workplace injuries (Wash. Rev. Code § 51.04.010). However, employers are not immune from lawsuits if the “injury results to a worker from the deliberate intention of [their] employer to produce such injury” (Wash. Rev. Code § 51.24.020). The Court of Appeals affirmed, finding that Defendant knew of asbestos hazards, which did not amount to actual knowledge that injury was certain to occur. The Court of Appeals also noted that Plaintiff’s medical expert conceded “that asbestos-related disease is never certain to result from asbestos exposure or even from pleural plaques.”

In reversing summary judgment in favor of Defendant, the Supreme Court of Washington overruled its prior decision in Walston v. Boeing Co., 334 P.3d 519 (Wash. 2014), where it held that “no employee could sue for a latent disease like mesothelioma because they could never satisfy the required level of certainty.” In effect, defendant employers would prevail as employees could not sue for injuries involving latent diseases, such as cancer, regardless of their employer’s intent. In Cockrum, the Washington Supreme Court held that “virtual certainty is sufficient to prove the employer’s actual knowledge that injury was certain to occur” only in latent disease cases. Thus, under the exception provided in Wash. Rev. Code § 51.24.020, a tort cause of action is possible when an employer deliberately causes injury in the form of disease. Id.

The evidence showed that before and contemporaneous with Plaintiff’s asbestos exposures, Defendant knew exposure to asbestos was hazardous and that asbestos-related diseases could manifest many years after exposure. Additionally, Defendant had a medical monitoring program, which served as evidence that Defendant’s employees were developing asbestos disease symptoms, including thickened pleura, calcified pleural plaques, fibrosis in the lungs, and asbestos-related diseases, including asbestosis and early mesothelioma. As such, the Court found that Defendant knew of the harms of asbestos in its facilities before and at the same time of Plaintiff’s injuries.

Ultimately, the Washington Supreme Court held that virtual certainty is sufficient to prove actual knowledge in latent disease cases.  Employers are shielded from liability when injuries result from accidents but are accountable in the narrow circumstances where there is deliberate intent to injure. Virtual certainty that a latent disease will occur may be proven by:

1. the employer’s knowledge of ongoing, repeated development of symptoms known to be associated with the development of latent disease over time;
2. the employer’s knowledge of symptoms developing in employees similarly situated to the plaintiff-employee;
3. the timing of such symptoms developing prior to or contemporaneous with the plaintiff-employee’s exposure(s); and
4. whether the exposure arises from a common major cause within the employer’s control.

Additionally, the actual knowledge prong of the deliberate injury exception is satisfied where an employer has sufficient knowledge of the hazards of exposure, the existence of symptoms linked to latent disease, and the causal relationship between the two for the employer to form actual knowledge disease is virtually certain to occur. A plaintiff satisfies the deliberate injury exception under Wash. Rev. Code § 51.24.020 if it can establish that its employer had actual knowledge that latent diseases are virtually certain to occur and willfully disregarded such knowledge.

Moving forward, employers in Washington need to be cautious as they can no longer depend on a virtually impregnable workers’ compensation bar for cases filed by employees who allege latent disease as a result of work performed on the employers’ premises. These employers should expect to be added to more latent disease lawsuits and also potentially be on the lookout for amended complaints in active cases in which they may become involved.