(concurring, with whom Marshall, C.J., joins). In Commonwealth v. Cass, 392 Mass. 799, 808 (1984), the court extended the vehicular homicide statute to include a viable fetus. See G. L. c. 90, § 24G (b). I joined in the dissent to that case, see id. at 809 (Wilkins, J., dissenting, with whom Liacos and Abrams, JJ., joined), because “[t]he public policy of the Commonwealth in the creation of crimes is not for this court to determine, but for the Legislature.” Commonwealth v. Corbett, 307 Mass. 7, 8 (1940).
Subsequently, in Commonwealth v. Lawrence, 404 Mass. 378 (1989), the court affirmed convictions of the murder in the first degree of a sixteen year old girl and the involuntary manslaughter of her twenty-seven week old fetus. Id. at 397. In my concurrence to that case, I reiterated my commitment to the views expressed by the dissent in Cass, and I noted that “[t]he court’s decision does not make clear what one must know, or should know, about the pregnancy, the condition of the fetus, and viability at the time of the acts of violence.” Lawrence, supra at *693399 (Abrams, J., concurring), citing Colautti v. Franklin, 439 U.S. 379, 390 (1979); Hollis v. Commonwealth, 652 S.W.2d 61, 64 (Ky. 1983).
Given that Cass and Lawrence remain the law of this Commonwealth, I concur in the court’s decision in the instant case. If one takes as a premise that a viable fetus in útero can be the victim of a homicide, then the court’s legal conclusions follow. However, I continue to adhere to the views expressed in the dissent in Cass and in my concurrence in Lawrence.
If a “person of ordinary intelligence” cannot determine that “his contemplated conduct is forbidden” by a law, then that law runs afoul of the due process required by our Constitution. See Colautti v. Franklin, supra. This case, like Cass and Lawrence, does not directly raise the issue of the scienter required for a conviction of homicide of a viable fetus in útero because the defendant was convicted of involuntary manslaughter. “The Commonwealth need only prove wanton and reckless conduct resulting in the death of a person. Wantonness and recklessness are determined by the conduct involved . . . .” Ante at 691.
However, the court also writes that “[t]he Commonwealth reasonably could not be required to prove that the defendant knew the fetus was viable because viability is an issue that involves a medical judgment.” Ante at 691. In support of this dictum, the court quotes my concurrence in Lawrence, supra at 399 (Abrams, J., concurring), that “[t]he mental element needed for conviction of murder cannot depend on a medical determination that can only be made by experts after the fact.” Ante at 691.
It was the concern that a person of ordinary intelligence might not be able to determine that he or she was committing two homicides that prompted me to write the words quoted by the court. See Lawrence, supra. Where proof offered at a criminal trial focuses on the victim’s medical status and not the defendant’s acts and state of mind, I think the court strays from the purposes of the criminal laws. “The focus of a criminal trial must be on the defendant’s mental state, not the victim’s physical condition.” Id.
As I observed in Lawrence, supra, “[sjuch issues . . . are not before us in this case. They await a case-by-case determination.” However, the fact that such issues continue to lurk in the law of homicide as this court has extended that law suggests to me that the creation of crimes is best left to the Legislature, as it always had been until Cass, supra.