The opinion
MOSK, J.
I concur generally in the opinion of the court and altogether in its judgment.
I write separately because, unlike my colleagues, I would resolve an issue of substantial importance to the jurisprudence of the death penalty in California and, indeed, in the United States as a whole.
Part of the Bill of Rights adopted in 1789, the cruel and unusual punishments clause of the Eighth Amendment to the United States Constitution, which was subsequently held applicable to the states through the due process clause of the Fourteenth Amendment, prohibits the infliction of penalties so described.
In Penry v. Lynaugh (1989) 492 U.S. 302 [ 109 S.Ct. 2934 , 106 L.Ed.2d 256 ] (hereafter sometimes Penry), the United States Supreme Court explained the cruel and unusual punishments clause and its scope and interpretation. “At a minimum,” it “prohibits punishment considered cruel and unusual” at common law “at the time the Bill of Rights was adopted.” (Id. at p. 330 [ 109 S.Ct. at p. 2953 ].) But it is “not limited” thereto. (Ibid.) It “also recognizes the ‘evolving standards of decency that mark the progress of a maturing society.’ ” (Id. at pp. 330-331 [ 109 S.Ct. at p. 2953 ], quoting Trop v. Dulles (1958) 356 U.S. 86, 101 [ 78 S.Ct. 590, 598 , 2 L.Ed.2d 630 ] (plur. opn.).) “In discerning those ‘evolving standards,’ ” courts “have looked,” and indeed should look, to “objective evidence of how our society views a particular punishment today” for a particular class of persons. (Penry v. Lynaugh, supra, 492 U.S. at p. 331 [ 109 S.Ct. at p. 2953 ]; see id. at pp. 329-330 [109 S.Ct. at pp. 2952-2953]). “The clearest and most reliable objective evidence of contemporary values is the legislation enacted by the country’s legislatures.” (Id. at p. 331 [ 109 S.Ct. at p. 2953 ].)
A decade ago, Penry held that the cruel and unusual punishments clause did not, at that time, prohibit execution of a sentence of death against mentally retarded persons. In doing so, it conceded that the federal constitutional provision might indeed impose such a bar as for some such persons, *1019 namely, those “who are profoundly or severely retarded and wholly lacking the capacity to appreciate the wrongfulness of their actions”—who are generally excused from criminal responsibility in the first place through the defense of insanity. (Penry v. Lynaugh, supra, 492 U.S. at p. 333 [ 109 S.Ct. at p. 2954 ].) But it declined to go further. It was unable to discern that “ ‘evolving standards of decency’ ” had, in fact, evolved far enough to shield mentally retarded persons as such from the ultimate sanction. (Id. at pp. 330-331 [ 109 S.Ct. at p. 2953 ], quoting Trop v. Dulles, supra, 356 U.S. at p. 101 [ 78 S.Ct. at p. 598 ] (plur. opn.).) For, at that time, it could not discover the emergence of any “national consensus” on the point: In addition to a single federal statute, in the form of the Anti-Drug Abuse Act of 1988, then recently passed by Congress, which provided that “[a] sentence of death shall not be carried out upon a person who is mentally retarded” ( 21 U.S.C. § 848 (l)), only two of the states that authorized the sentence of death—about 5 percent of the total—had enacted legislation that prohibited its execution against mentally retarded persons. (Penry v. Lynaugh, supra, 492 U.S. at pp. 333-334 [109 S.Ct. at pp. 2954-2955].)
Today, however, I would hold that the cruel and unusual punishments clause now prohibits execution of a sentence of death against mentally retarded persons. I am able to discern that, since Penry , “evolving standards of decency” have indeed evolved sufficiently in this area. Indeed, I cannot do otherwise. For I find that the requisite “national consensus” has, in fact, emerged. As I write, at least 11 of the states that authorize the sentence of death—about 29 percent of the total—have enacted legislation that prohibits its execution against mentally retarded persons. More important, however, is what Congress has done. In Congress, the representatives of the states speak for the nation as a whole. In the face of Penry , Congress has amended the Anti-Drug Abuse Act of 1988. It has not subjected the statutory provision cited above to repeal, but rather has caused it to be reenacted, to declare, now as originally, that “[a] sentence of death shall not be carried out upon a person who is mentally retarded” ( 21 U.S.C. § 848 (l)). After Penry , it enacted the Violent Crime Control and Law Enforcement Act of 1994. In this statute, it expands authorization of the sentence of death. But, as in its earlier statute, it also prohibits its execution against mentally retarded persons, in identical terms: “A sentence of death shall not be carried out upon a person who is mentally retarded.” ( 18 U.S.C. § 3596 (c).) Whatever conditions or qualifications that may arguably be present in analogous state legislation are surely absent from the federal. 1
Turning to the case at bar, I would not pass on the merits of Smithey’s claim that the cruel and unusual punishments clause prohibits execution of *1020 the sentence of death on the ground that he is mentally retarded. Trial was conducted in the period prior to the decision in Penry—at a time, that is, before “evolving standards of decency” had evolved far enough, before the requisite “national consensus” had emerged. As a result, Smithey did not have an incentive or an opportunity to present the issue in terms that might prove adequate today. Neither did the People have an incentive or an opportunity to respond in similar terms. Now, each does.
I would therefore allow Smithey to raise his claim anew, via a petition for writ of habeas corpus, which is available to enforce prohibitions of a “fundamental . . . constitutional type” (In re Harris (1993) 5 Cal.4th 813, 828 [ 21 Cal.Rptr.2d 373 , 855 P.2d 391 ]), including, of course, that of the Eighth Amendment against cruel and unusual punishments.
Appellant’s petition for review by the Supreme Court was denied September 15, 1999, and the opinion was modified to read as printed above.
The cruel or unusual punishment clause of section 17 of article I of the California Constitution prohibits the infliction of any penalty so described—which goes beyond punishment that is “cruel and unusual” under the Eighth Amendment to punishment that is “cruel or *1020 unusual.” The state constitutional provision is broader than its federal constitutional counterpart. (E.g., People v. Anderson (1972) 6 Cal.3d 628, 634-639 [ 100 Cal.Rptr. 152 , 493 P.2d 880 ].) Hence, it necessarily extends at least as far in its protection. That means that it, too, prohibits execution of a sentence of death against mentally retarded persons. That no similar statutory prohibition has yet been enacted by the Legislature does not undermine this conclusion. Just as the state constitutional provision cannot be trumped by legislative action (see id. at p. 640), neither can it be trumped by legislative /«action.