Does the error in failing to instruct the jury on involuntary manslaughter constitute a reversible error?

Moreover, the error in failing to instruct the jury on involuntary manslaughter was prejudicial. The failure to instruct on a lesser included offense is reversible error if there is a reasonable probability that the defendant would have obtained a more favorable result in the absence of the error. (People v. Breverman (1998) 19 Cal.4th 142, 176-177, 77 Cal.Rptr.2d 870, 960 P.2d 1094; People v. Watson (1956) 46 Cal.2d 818, 836, 299 P.2d 243.)

As discussed ante, the evidence supports an inference that the killing was unintentional as well as it supports the opposite inference. What the evidence does show unequivocally is that, unless she used excessive force to defend herself, defendant did "an act, the natural consequences of which are dangerous to life, which act was deliberately performed by a person who knows that his conduct endangers the life of another and who acts with conscious disregard for life.... [Citations.]" (People v. Watson (1981) 30 Cal.3d 290, 300, 179 Cal.Rptr. 43, 637 P.2d 279, internal quotation marks omitted.) That is, she acted with implied malice, on which the jury was instructed.