¶1(concurring). I continue to adhere to the views expressed by the dissent in Commonwealth v. Cass, 392 Mass. 799, 808 (1984). “The question whether the killing of a viable fetus [in the present circumstances] should be a separate crime is for the Legislature as a matter of wise social policy,” id. at 809 (Wilkins, J., dissenting), subject to the constitutional limitations that this court and the United States Supreme Court have set. “The 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). Nevertheless, the Casscase is the law of this Commonwealth.
¶2*398The defendant makes three arguments with respect to his conviction for the death of the fetus. First, he argues that Massachusetts law does not recognize a fetus as a human being for purposes of construing the common law crime of murder. This argument is clearly incorrect in light of Cass, which addressed not only the vehicular homicide statute but also the common law. See Cass, supra at 807. Second, the defendant argues that, if the court is to make feticide punishable as homicide, it should do so only prospectively because the law gave the perpetrator insufficient notice that such conduct was forbidden. This argument is similarly without merit, as Cassgave ample notice that there would thenceforth be criminal liability for feticide in these circumstances. Third, the defendant argues that Roe v. Wade, 410 U.S. 113 (1973), precludes a determination that a fetus is a human being for purposes of common law murder.
¶3This case, as well as Cass, criminalizes acts of violence perpetrated against the mother. The defendant cannot claim that his acts were performed for health reasons or that they were the result of a medical or personal decision by a pregnant woman. Thus, the acts of violence in murdering the pregnant woman are not acts protected by constitutional or statutory law.
¶4This is a relatively easy case in which to impose criminal liability because the defendant concedes that the fetus was viable, and does not argue that the perpetrator was unaware that the victim was pregnant. Thus, the court need not and does not discuss a scienter requirement with respect to the finding of viability. In other cases, that issue may arise in a constitutional framework. See Colautti v. Franklin, 439 U.S. 379, 390 (1979).
¶5The 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. See Colauttiv. Franklin, supra;Hollis v. Commonwealth, 652 S.W.2d 61, 64 (Ky. 1983). The mental element needed for conviction of murder cannot depend on a medical determination that can only be made by experts after the fact. The focus of a criminal trial must be on the defendant’s mental state, not the victim’s physical condition. Such issues, however, are not before us in this case. They await a case-by-case determination.
¶6 As far as I can determine, South Carolina is the only other State which has extended by case law the definition of homicide to include a viable fetus. See State v. Horne, 282 S.C. 444 (1984). Compare Keeler v. Superior *398Court, 2 Cal. 3d 619 (1970); State v. McCall, 458 So. 2d 875 (Fla. Dist. Ct. App. 1984); People v. Greer, 79 Ill. 2d 103 (1980); Hollis v. Commonwealth, 652 S.W.2d 61 (Ky. 1983); State v. Gyles, 313 So. 2d 799 (La. 1975); State v. Soto, 378 N.W.2d 625 (Minn. 1985); State ex rel. Atkinson v. Wilson, W.Va. (1984) (332 S.E.2d 807 [W.Va. 1984]).
¶7This case does not implicate a woman’s constitutional right of privacy or her constitutional right to terminate a pregnancy pursuant to Roe v. Wade, 410 U.S. 113 (1973). Roeis an integral part of our jurisprudence. See Moe v. Secretary of Admin. & Fin., 382 Mass. 629, 647 (1981). This case does not involve an intrusion by the State into the doctor/patient relationship. See Akron v. Akron Center for Reproductive Health, Inc., 462 U.S. 416 (1983). Casscorrectly recognized that there are Federal and State constitutional limitations in extending criminal statutes. See id.at 807 n.11.