What is the test for a jury to find a defendant guilty of a charge of attempted voluntary manslaughter?

Here, however, the jury found the defendant guilty of attempted voluntary manslaughter, rejecting a charge of attempted murder. Relying on a [227 Cal.App.3d 815] theory of imperfect self-defense (see People v. Flannel (1979) 25 Cal.3d 668, 160 Cal.Rptr. 84, 603 P.2d 1), they necessarily accepted defendant's testimony that he believed himself threatened, but concluded such belief was not objectively reasonable. Thus, while we believe the court erred in excluding the evidence, the jury's verdict convinces us that the error did not prejudice defendant.