Lay Witness Testimony Acceptable to Prove Disease Arose 'Naturally'

In a case of first impression, the Washington Supreme Court this week clarified that an injured worker does not need expert medical testimony to establish that his occupational disease arose “naturally” from his employment so long as he has an expert who says his condition was “proximately" caused by work. Washington’s Industrial Insurance Act requires that a worker prove his illness arose “naturally and proximately” out of his employment in order to receive benefits for an occupational disease. Thirty years ago, the Washington Supreme Court rule...