¶ 1 Under Arizona law, if the death penalty is not imposed for first degree murder, the only other possible sentences are life with the possibility of release after a specified
I.
¶ 2 Edward John Sanders was indicted in 2000 for sexual assault and murder. The State filed a notice of intent to seek the death penalty and alleged two aggravating circumstances: that Sanders had committed the offense in an especially heinous, cruel, or depraved manner, see A.R.S. § 13-703(F)(6) (Supp.2000), 2 and that at the time of the offense Sanders was an adult and the victim was seventy years of age or older, see A.R.S. § 13-703(F)(9). The State later withdrew the notice seeking the death penalty.
¶ 3 Before the case proceeded to trial, two different cases and two different legislative enactments radically affected Arizona’s first degree murder sentencing scheme. In 2002, the Supreme Court of the United States held Arizona’s capital sentencing scheme unconstitutional because judges, not juries, determined the existence of the aggravating circumstances necessary to impose a death sentence.
Ring v. Arizona,
¶ 4 In 2003, this Court held that under the
pre-Ring
statutory scheme, a judge imposing a non-capital sentence for first degree murder could consider only the aggravators set forth in A.R.S. § 13-703(F) when deciding the appropriate punishment.
State v. Vira-montes,
¶ 5 On June 11, 2004, a jury found Sanders guilty of first degree murder and other offenses. On June 24, 2004, the United States Supreme Court held Washington’s non-capital sentencing scheme unconstitutional under the Sixth Amendment.
Blakely v. Washington, 542
U.S. 296,
¶ 6 The State petitioned for special action review in the court of appeals. That court accepted jurisdiction and held that
Blakely
does not apply to Arizona’s non-capital, first degree murder sentencing scheme because a trial judge is not required to make findings in addition to those made by the jury in its guilty verdict in deciding between a life and a natural life sentence.
State v. Fell (Sanders ),
¶7 Sanders petitioned for review of the Blakely holding and the State cross-petitioned for review of the retroactivity holding. We granted both petitions because the issues are of statewide importance. We have jurisdiction pursuant to Article 6, Section 5(3) of the Arizona Constitution and A.R.S. § 12-120.24 (2003).
II.
A.
¶ 8 As we noted last year,
Apprendi v. New Jersey,
¶9 In Blakely, the Supreme Court held that
the “statutory maximum” for Apprendi purposes is the maximum sentence a judge may impose solely on the basis of the facts reflected in the jury verdict____In other words, the relevant “statutory maximum” is not the maximum sentence a judge may impose after finding additional facts, but the maximum he may impose without any additional findings. When a judge inflicts punishment that the jury’s verdict alone does not allow, the jury has not found all the facts “which the law makes essential to the punishment,” and the judge exceeds his proper authority.
542 U.S. at -,
B.
¶ 10 Determining the “statutory maximum” for
Apprendi
/
Blakely
purposes is of necessity a matter
of
statutory construction.
See Brown (McMullen),
A person guilty of first degree murder as defined in § 13-1105 shall suffer death or imprisonment in the custody of the state department of corrections for life as determined and in accordance with the procedures provided in subsections B through G of this section. If the court imposes a life sentence, the court may order that the defendant not be released on any basis for the remainder of the defendant’s natural life. An order sentencing the defendant to natural life is not subject to commutation or parole, work furlough or work release. If the court does not sentence the defendant to natural life, the defendant shall not be released on any basis until the completion of the service of twenty-five calendar years if the victim was fifteen or more years of age and thirty-five years if the victim was under fifteen years of age.
¶ 11 We interpreted this statutory scheme in
State v. Ring,
¶ 12 The first degree murder sentencing statute in effect in 2000 expressly required the finding of at least one aggravating circumstance before a death sentence could be imposed.
See
A.R.S. § 13-703(E) (allowing sentence of death only if the “court finds one or more aggravating circumstances ... and that there are no mitigating circumstances sufficiently substantial to call for leniency”);
State v. Gretzler,
¶ 13 Sanders nonetheless argues that life is the “presumptive” sentence for first degree murder and that natural life is an “aggravated” sentence. The notion of a presumptive sentence arises from the statutes governing punishment for felonies other than first degree murder, which generally provide that a defendant “shall” receive a specific term of imprisonment.
See
A.R.S. §§ 13-701 (2001) (governing sentences for class 2, 3, 4, 5 and 6 felonies) and 13-710 (2001) (governing sentences for second degree murder). The presumptive sentence may be either increased or reduced based upon findings of specific aggravating or mitigating circumstances. A.R.S. § 13-702(A) (Supp.2004). Thus, we held in
Brown (McMullen)
that the “presumptive sentence” under § 13-701 is the “maximum sentence” for purposes of
Apprendi
analysis.
¶ 14 However, the statutes governing sentencing for first degree murder are markedly different. While §§ 13-701 and 13-710 provide that a specific sentence “shall” be imposed for various felonies in the absence of a finding of either the prior criminal history described in A.R.S. § 13-604 or the aggravating circumstances specified in § 13-702, § 13-703 contains no similar language. The statute does not provide that a defendant “shall” receive life unless certain facts are found. To the contrary, the statute provides that “[i]f the court imposes a life sentence, the court may order that the defendant not be released on any basis for the remainder of the defendant’s- natural life.” A.R.S. § 13-703(A) (emphasis added). Had the legislature intended to require a specific finding be made before a natural life sentence could be imposed, it surely would have said so specifically, as it did in the statutes governing sentencing for felonies other than first degree murder.
¶ 15 Unlike the determinate sentencing scheme generally applicable to other felonies, § 13-703(E) provides the superior court with the discretion to sentence an offender within a range — from life to natural life — for non-capital first degree murder.
See State v. Wagner,
C.
¶ 16
Viramontes
held that under the
pre-Ring
version of the first degree murder
¶ 17 In holding that a judge deciding between a life and natural life sentence can consider only the factors in § 13-703(F), Vi-ramontes neither expressly nor impliedly held that a court must find any specific aggravating factor to impose a natural life sentence. The special verdict explains the judge’s reasons for imposing the sentence, but the statute does not require any specific factual finding before a defendant is statutorily eligible for a natural life term. As Justice Sealia explained in Blakely, there is an important constitutional difference between factual findings necessary to make a defendant eligible for a specified range of penalty and those that shape a trial judge’s discretion within that range:
[T]he Sixth Amendment by its terms is not a limitation on judicial power, but a reservation 'of jury power. It limits judicial power only to the extent that the claimed judicial power infringes on the province of the jury. Indeterminate sentencing does not do so. It increases judicial discretion, to be sure, but not at the expense of the jury’s traditional function of finding the facts essential to lawful imposition of the penalty. Of course indeterminate schemes involve judicial factfinding, in that a judge (like a parole board) may implicitly rule on those facts he deems important to the exercise of his sentencing discretion. But the facts do not pertain to whether the defendant has a legal right to a lesser sentence — and that makes all the difference insofar as judicial impingement upon the traditional role of the jury is concerned.
542 U.S. at -,
¶ 18 Sanders argues that the requirement in § 13-703(D) that the superior court return a special verdict is meaningless unless some specific factual finding is required before a natural life sentence is imposed. A statutory requirement that a judge make findings, however, does not mean that any specific finding is necessary for imposition of the sentence.
6
The statutory scheme restricted the factors that the superior court could consider in choosing between life and natural life sentences for non-capital first degree murder. Given the requirement of the former statute that only the aggravating factors listed in § 13-703(F) be considered in determining whether a life or natural life sentence was to be imposed,
see Viramontes,
III.
¶20 The remaining question is what factors the judge may consider in exercising his discretion to sentence a defendant to either life or natural life. Viramontes held that the former version of § 13-703 limited trial judges to the aggravating factors listed in subsection (F) of that statute. Several months after that opinion was issued, the legislature enacted what is now A.R.S. § 13-703.01(Q)(2) (Supp.2004), providing that “[i]n determining whether to impose a sentence of life or natural life,” a trial court “[sjhall consider the aggravating and mitigating circumstances listed in section 13-702 and any statement made by a victim.” 2003 Ariz. Sess. Laws, ch. 225, § 2. The State argues that § 13-703.01(Q) should be applied when the superior court determines Sanders’ sentence.
A.
¶ 21 “No statute is retroactive unless expressly declared therein.” A.R.S. § 1-244 (2002). Nothing in 2003 Ariz. Sess. Laws, ch. 225, expressly declares that § 13-703.01(Q) is to be retroactively applied. In contrast, when the legislature amended the death penalty sentencing scheme after Ring II, it carefully detailed the application of various provisions of the new statute to pending cases. 2002 Ariz. Sess. Laws, 5th Spec. Sess., ch. 1, § 7.
¶ 22 However, the absence of any legislative declaration about retroactivity does not end our inquiry.
This court has previously created an exception to the general rule requiring express language of retroactivity. Enactments that are procedural only, and do not alter or affect earlier established substantive rights may be applied retroactively. Even if a statute does not expressly provide for retroactivity, it may still be applied if merely procedural because litigants have no vested right in a given mode of procedure.
Aranda v. Indus. Comm’n,
¶ 23 We conclude that the change was not simply procedural. Under the law in effect at the time that Sanders committed his crime, the superior court could consider only the ten aggravators specified in § 13-703(F) in making the choice between a life and natural life sentence. Section 13-703.01(Q) instead empowers the trial court to take into account the twenty-one aggravators listed in § 13-702(C). Because the new statute thus allows the imposition of a sentence on the basis of factors that the prior law excluded from consideration, it is plainly a substantive change in the law.
See State v. Correll,
B.
¶ 24 We have recognized another exception to the general rule against retroactive application of a statutory amendment when the amendment is simply a “clarification” of existing law. “An amendment which, in effect, construes and clarifies a prior statute will be accepted as the legislative declaration of the original act.”
City of Mesa v. Killingsworth,
¶ 25 This rule of statutory interpretation applies, however, only when the “origi
nal
C.
¶26 Finally, the State argues that Vira-montes was wrongly decided and urges that we overrule it. We decline to do so.
The doctrine of stare decisis, which requires us to give weight to previous decisions addressing the same issue, seeks to promote reliability so that parties can plan activities knowing what the law is. Importantly, our deference to precedent is strongest when prior decisions construe a statute. [E]ven those who regard stare decisis with something less than enthusiasm recognize that the principle has even greater weight where the precedent relates to interpretation of a statute.
Galloway,
¶ 27 The legislature is, of course, free at any time to respond to our statutory interpretations by changing the relevant statute. That is precisely what occurred here. By enacting § 13-703.01(Q), the legislature restricted the application of the holding in Vi-ramontes to those cases arising before the effective date of the new statute. Thus, there is no reason to revisit our prior decision.
TV.
¶ 28 For the reasons above, the opinion of the court of appeals is affirmed, and the case is remanded to the superior court for further proceedings consistent with this opinion.
Notes
. The period depends upon the age of the murdered person. If the murdered person is fifteen or more years of age, the period is twenty-five calendar years; if less than fifteen years of age, the period is thirty-five years. A.R.S. § 13— 703(A).
. Unless noted otherwise, all citations to A.R.S. § 13-703 in this opinion refer to the version of the statute in place at the time this crime was committed in 2000.
. Although neither the superior court’s written order nor the transcripts of the proceedings below are explicit on this point, the parties agreed at oral argument in the court of appeals that the superior court so held.
. The current version of the statute similarly requires that the "trier of fact” find one of the statutory aggravating circumstances before the death penalty can be imposed. A.R.S. § 13-703(E) (Supp.2004).
.
State
v.
Ovind,
. The Supreme Court has reached a similar conclusion with respect to the federal sentencing guidelines. In
United States v. Booker,
the Court, after holding that the provision making the guidelines mandatory violated the Sixth Amendment, severed that provision, thus making the guidelines "effectively advisory.” — U.S. -, — - —,
. When the sentencing scheme places discretion in the superior court to sentence within a speci
fied range, an appellate court has the power to review the sentence for an abuse of discretion.
See State v. Grier,