Vaughn v. Jonas (1948) 31 Cal.2d 586, was a civil lawsuit for battery where the trial court erroneously instructed on self-defense by telling the jury that the defendant was permitted to use only the amount of force reasonably necessary to repel the attack, rather than the amount of force that appeared reasonably necessary to the defendant. (Id. at pp. 599-600.)
The Supreme Court concluded the instructional error was harmless.
"It does not seem reasonably possible that the jury was misled by the error in question to defendant's prejudice. From the verdict awarding punitive damages it appears that the jury necessarily found that the defendant acted maliciously. Exemplary damages, under the instructions given on that subject, could not have been awarded unless the jury found that the shooting was actuated by malice; if it was actuated by malice it was unjustified on any theory. We the Supreme Court do not find any persuasive basis for believing that the finding as to malice was influenced to any extent whatsoever by the erroneous statements of law. In view of the verdict, therefore, and our duty under . . . the state Constitution, we cannot hold that the error in question requires reversal of the judgment." (Id. at pp. 600-601.)