concurring.
Today’s decision requires that I repeat my disagreement with the various theories expounded by my brethren in the Ford, Garcia, and Polimeni decisions. Commonwealth v. Ford, 474 Pa. 480, 486, 378 A.2d 1215, 1218 (1977) (NIX, J., dissenting); Commonwealth v. Garcia, 474 Pa. 449, 471, 378 A.2d 1199, 1210 (1977) (NIX, J., dissenting); Commonwealth v. Polimeni, 474 Pa. 430, 449, 378 A.2d 1189, 1199 (1977) (NIX, J., dissenting). I remain unconvinced that the adherence to a lesser included offense analysis or to a theory of a jury’s “mercy-dispensing power” compels an unconditional right in all murder trials to an involuntary manslaughter instruction upon request by the defense. Nor do I believe that an instruction for involuntary manslaughter should be allowed simply because there may be a reasonable basis in the evidence to support a finding of involuntary manslaughter. See Commonwealth v. Ford, supra, 474 at 485, 378 A.2d at 1216 (POMEROY, J., announcing the decision of this Court); Commonwealth v. Garcia, supra, 474 Pa. at 470, 378 A.2d at 1210 (POMEROY, J., concurring); Commonwealth v. Polimeni, supra, 474 Pa. at 447, 378 A.2d at 1191 (POMER-OY, J., announcing the decision of this Court). I do, however, accept the conclusion that the requested manslaughter instruction in this case was improperly denied, because such a charge was essential under the evidence presented to inform the jury of the competing contentions raised in the lawsuit. I therefore agree that the second degree murder conviction returned in this action must be reversed.
In the present lawsuit, appellant did not contest that she caused the death of Ernest Barnes or that the killing did not *198constitute a criminal homicide. The critical issue at trial was whether there was a malicious killing (i. e., one committed in the course of the commission of the felony of robbery) or a nonmalicious unintentional killing (involuntary manslaughter). Thus, we are here presented with a situation where the factual dispute centers upon the presence or absence of the element of malice, the element which distinguishes the higher grade of homicide from the lesser grade.* This is precisely the type of situation where an instruction on the lesser offense, upon request, is warranted. See Commonwealth v. Manning, 477 Pa. 495, 500, 384 A.2d 1197, 1199 (1978) (NIX, J., dissenting); Commonwealth v. Gartner and Pfaff, 475 Pa. 512, 516 n. 3, 381 A.2d 114, 125 n. 3 (1977) (NIX, J., concurring and dissenting). Where the factual posture effectively excludes a realistic possibility of an acquittal, as is the case here, to deprive the accused of her right to allow the jury to consider the lesser offense is tantamount to depriving her of a defense. Where instructions on the lesser offense are given, the verdict will necessarily reflect the jury’s resolution of the disputed factual issue at trial. The finding of the higher verdict would evidence the prosecutor’s success in establishing the disputed element. Likewise the return of a guilty verdict on the lesser offense would reflect his failure to establish that element which distinguishes the two offenses.
A rational basis theory would allow the instruction of involuntary manslaughter even though the dispute relates to an element which is common to both the higher and lesser degree of a crime. See Commonwealth v. Gartner and Pfaff, 475 Pa. 512, 516 n. 3, 381 A.2d 114, 125 n. 3 (1977) (NIX, J., concurring and dissenting).