Since its recognition in the 1980s, Washington's "loss of chance" cases have been used to lessen the required showing of "but for" causation in medical negligence cases. This issue was brought to a head in Rash v. Providence Health & Services, et al. Rash was a medical negligence/wrongful death case claiming that a failure by the hospital to provide a patient's routine medication following a knee arthroscopy resulted in death and a "loss of chance" of survival. The hospital successfully moved for dismissal of the loss of chance claim and plaintiffs appealed.
Plaintiffs argued on appeal that in loss of chance cases the burden should be reduced to a showing that the defendant's conduct was "a substantial factor" in bringing about the alleged harm. On behalf of Providence Sacred Heart Medical Center, Witherspoon • Kelley was successful in safeguarding the traditional legal principles – plaintiffs must still show that the defendant's conduct was, in fact, a cause of the alleged injury.