What is the test for reasonable implied assumption of risk?

The initial question presented in this petition is whether the doctrine of reasonable implied assumption of risk survives in the era of comparative fault. We had occasion to touch on the subject once before (Rudnick v. Golden West Broadcasters (1984) 156 Cal.App.3d 793, 202 Cal.Rptr. 900), but a resolution of the matter was not essential to that decision. It is now, however; and the answer is, "Yes."

Courts and legal scholars have traditionally recognized three forms of assumption of risk. Express assumption of risk is exactly what the term describes: Where "the potential plaintiff agrees not to expect the potential defendant to act carefully, thus eliminating the potential defendant's duty of care, and acknowledging the possibility of negligent wrongdoing," the potential plaintiff has expressly assumed the risk of injury. (Coates v. Newhall Land & Farming, Inc. (1987) 191 Cal.App.3d 1, 7-8, 236 Cal.Rptr. 181.)

Reasonable implied assumption of risk is the inferred agreement to relieve a potential defendant of a duty of care based on the potential plaintiff's reasonable conduct in encountering a known danger. A second variety of implied assumption of risk is labeled unreasonable. (Rudnick v. Golden West Broadcasters, supra, 156 Cal.App.3d at pp. 798-799, 202 Cal.Rptr. 900.) After a brief prefatory digression, we will explain the importance of the distinction between them in determining the rights of the parties.