What is the current state of the law on unavoidable accident?

The cases decided by the district courts of appeal subsequent to Parker v. Womack have held that it is not error to give an instruction on unavoidable accident and that it is not error to refuse it. This poses the obvious question 'Why give it at all?' We think the answer is that it should not be given. In unbroken sequence the cases have held that instructions on negligence are sufficient. That had been the reason for holding that it is not error to give the instruction, or to refuse it. Ever since Parker v. Womack the courts have not considered whether there was evidence of an unavoidable cause which could be found to have been the sole proximate cause of the accident. In that case and in the cases we have listed in which the giving of the instruction was held not to be error there was no evidence of an extraneous cause that would have justified a finding that it was the sole proximate cause of the accident. To merely hold that giving the instruction was not error because absence of negligence and unavoidability are the same does not fully answer the problem. How can the courts be sure that the instruction does a plaintiff no harm and gives the defendant no advantage when there is no evidence of an outside, unavoidable cause to which the instruction could relate? Is there not an implication that unavoidable accident is something different from negligence when the court, after instructing on negligence, gives another instruction commencing: 'In law we recognize what is termed an unavoidable or inevitable accident'? The only possible negative answer to this question is that the instruction is not deceptive because it proceeds to explain that the rule of 'unavoidable or inevitable accident' really means nothing at all and should not have been mentioned in the first place.

Litigants charged with negligence have good reason to believe there is some advantage in having the jury instructed on unavoidability. No one knows whether the defendants who have prevailed in actions in which the instruction was given derived some undeserved benefit from it. We do not see how our courts can feel assured that all jurors can comprehend the meaning and proper application of the rule of unavoidability, nor can we see any virtue in giving an instruction which, admittedly, can do no good and may cause harm. While it may not be questioned that the instruction need not be given when the jury is fully instructed on negligence, a better reason for declining to give it would be that there is no evidence of unavoidability, if that be the fact. See Riley v. Berkeley Motors, Inc., 1 Cal.App.2d 217, 36 P.2d 398;

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