OPINION OF THE COURT
Mumia Abu-Jamal was convicted of first-degree murder in state court and sentenced to death. After exhausting state appeals, he filed a petition for a writ of habeas corpus under 28 U.S.C. § 2254. A divided panel of this court affirmed the denial of Abu-Jamal’s petition insofar as it challenged his conviction.
See Abu-Jamal v. Horn,
*372
On his death penalty challenge,
1
the District Court found the Pennsylvania Supreme Court’s order denying post-conviction relief involved an unreasonable application of United States Supreme Court precedent.
See
28 U.S.C. § 2254(d)(1). We affirmed the District Court’s grant of habeas relief on the sentence,
see AbuJamal,
On January 19, 2010, the United States Supreme Court granted the Commonwealth’s petition for a writ of certiorari, vacated our judgment as to Abu-Jamal’s sentence, and remanded for further consideration.
Beard v. Abu-Jamal,
— U.S. -,
After further review, we conclude the Pennsylvania Supreme Court unreasonably applied
Mills v. Maryland,
I.
In 1982, a Pennsylvania jury convicted Abu-Jamal of the murder of Philadelphia Police Officer Daniel Faulkner.
See Abur-Jamal,
The Pennsylvania courts denied AbuJamal’s claims on direct appeal and collateral review.
Commonwealth v. Abu-Jamal,
Having exhausted state court remedies, Abu-Jamal filed a petition for a writ of habeas corpus under 28 U.S.C. § 2254 in the United States District Court for the Eastern District of Pennsylvania. He challenged the validity of his criminal conviction, his capital sentence, and the sufficiency of post-conviction review. He
*373
argued, among other things, that the sentencing phase of his trial violated the United States Constitution because the jury instructions and verdict sheet required jury unanimity in its findings with respect to the existence of mitigating circumstances. The District Court denied the petition as to the conviction and post-conviction proceedings but accepted AbuJamal’s mitigation instruction claim.
See Abu-Jamal v. Horn,
No. Civ. A. 99-5089,
Thereafter, the parties filed cross-petitions for writs of certiorari in the Supreme Court of the United States. The Supreme Court denied Abu-Jamal’s petition seeking review of his conviction,
see Abu-Jamal v. Beard,
— U.S.-,
Our review on remand is limited to whether the Pennsylvania Supreme Court unreasonably applied United States Supreme Court precedent in finding no constitutional defect in the jury instructions and verdict form employed in the sentencing phase of Abu-Jamal’s trial.
See
28 U.S.C. § 2254(d)(1);
Williams v. Taylor,
II.
Under the standard for habeas relief established by the Antiterrorism and Effective Death Penalty Act of 1996 (AED-PA), a state prisoner’s application for a writ of habeas corpus will be denied unless the adjudication of a claim in state court proceedings “(1) resulted in a decision that was contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States; or (2) resulted in a decision that was based on an unreasonable determination of the facts in light of the evidence presented in the State *374 court proceeding.” 28 U.S.C. § 2254(d)(1)-(2).
Under the first clause of § 2254(d)(1), “a state-court decision is contrary to [Supreme Court] precedent if the state court arrives at a conclusion opposite to that reached by th[e] Court on a question of law,” or “if the state court confronts facts that are materially indistinguishable from a relevant Supreme Court precedent and arrives at a result opposite to [the Court’s].”
Williams,
Accordingly, we consider only the second clause of § 2254(d)(1), and must determine whether the Pennsylvania Supreme Court’s decision to deny Abu-Jamal’s mitigation instruction claim “involved an unreasonable application of[] clearly established Federal law, as determined by the Supreme Court of the United States,” 28 U.S.C. § 2254(d)(1), in
Mills.
“Under § 2254(d)(l)’s ‘unreasonable application’ clause ... a federal habeas court may not issue the writ simply because that court concludes in its independent judgment that the relevant state-court decision applied clearly established federal law erroneously or incorrectly. Rather, that application must also be unreasonable.”
Williams,
In
Spisak,
the Supreme Court found no violation of
Mills
and consequently concluded the state court decision at issue, reaching the same conclusion, was not “‘contrary to, or ... an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States’ in Mills.”
III.
In
Mills,
the Supreme Court vacated a death sentence after finding there was “a substantial probability that reasonable jurors, upon receiving the judge’s instructions in this case, and in attempting to complete the verdict form as instructed, well may have thought they were precluded from considering any mitigating evidence unless all 12 jurors, agreed on the existence of a particular such circumstance.”
3
The verdict form at issue in
Mills
included a list of potentially mitigating circumstances, and spaces for the jury to check “yes” or “no” after each circumstance. Preceding the list, the form read “ ‘[biased upon the evidence we unanimously find that each of the following mitigating circumstances which is marked “yes” has been proven to exist ... and each mitigating circumstance marked “no” has not been proven....’”
Mills,
We conclude the verdict form and jury instructions in this ease likewise created a *376 substantial probability the jury believed it was precluded from finding a mitigating circumstance that had not been unanimously agreed upon. In relevant part, the first page of the verdict form used in AbuJamal’s trial stated:
(1) We, the jury, unanimously sentence the defendant to
[X] death
[ ] life imprisonment.
(2) (To be used only if the aforesaid sentence is death)
We, the jury, have found unanimously
[ ] at least one aggravating circumstance and no mitigating circumstance. The aggravating circumstance(s) is/are
[X] one or more aggravating circumstances which outweigh any mitigating circumstances. The aggravating circumstance(s) is/are
A.
The mitigating circumstance(s) is/are
A.
The second page listed ten potentially aggravating circumstances (a-j). A third page listed eight potentially mitigating circumstances (a-h). 6 Each of the potential aggravating or mitigating circumstance listed had a space next to it for the jury to place a checkmark if it found the aggravating or mitigating circumstance to exist. On the third and final page, there were twelve spaces for each juror to sign his or her name, and each did. The instructions given to the jury provided, in part:
Members of the jury, you must now decide whether the defendant is to be sentenced to death or life imprisonment. The sentence will depend upon your findings concerning aggravating and mitigating circumstances. The Crimes Code provides that a verdict must be a sentence of death if the jury unanimously finds at least one aggravating circumstance and no mitigating circumstance, or if the jury unanimously finds one or more aggravating circumstances which outweigh any mitigating circumstances. The verdict must be a sentence of life imprisonment in all other cases.
The [Cjommonwealth has the burden of proving aggravating circumstances beyond a reasonable doubt. The defendant has the burden of proving mitigating circumstances, but only by a preponderance of the evidence. This is a lesser burden of proof than beyond a reasonable doubt. A preponderance of the evidence exists where one side is more believable than the other side____
Now, the verdict is for you, members of the jury. Remember and consider all of the evidence giving it the weight to which it is entitled. Remember that you are not merely recommending a punishment. The verdict you return will actually fix the punishment at death or life imprisonment. Remember again that your verdict must be unanimous. It cannot be reached by a majority vote or by any percentage. It must be the verdict of each and everyone [sic] of you. Remember that your verdict must be a sentence of death if you unanimously find at least one aggravating circumstance and no mitigating circumstances. Or, if you unanimously find one or more aggravating circumstances which outweigh any mitigating circumstances. In *377 all other cases, your verdict must be a sentence of life imprisonment.
It is substantially probable the verdict form’s first page, especially “[w]e, the jury, have found unanimously ... one or more aggravating circumstances which outweigh any mitigating circumstances,” was read by the jury to mean that both aggravating and mitigating circumstances must be found unanimously. The jury instructions read similarly, stating: “The Crimes Code provides that a verdict must be a sentence of death if the jury unanimously finds at least one aggravating circumstance and no mitigating circumstance, or if the jury unanimously finds one or more aggravating circumstances which outweigh any mitigating circumstances.” And the portion of the form where the jury was instructed to identify any mitigating circumstances found — “The mitigating circumstance(s) is/are__” — was introduced by the words “[w]e, the jury, have found unanimously.” Moreover, the instructions throughout and repeatedly emphasized unanimity. In light of the language and parallel structure of the form and instructions in relation to aggravating and mitigating circumstances, it is notable that neither the verdict form nor the judge’s charge said or in any way suggested that the jury should apply the unanimity requirement to its findings of aggravating but not mitigating circumstances. This absence is also notable because the trial court distinguished between the two with respect to the proper burden of proof the jury should apply.
We conclude the verdict form together with the jury instructions read that unanimity was required in the consideration of mitigating circumstances and that there is a substantial probability the jurors believed they were precluded from independent consideration of mitigating circumstances in violation of Mills. We now compare the instructions at issue in Spisak with the verdict form and jury charge here to determine whether our conclusion is consistent with Spisak.
IV.
In
Spisak
the Supreme Court evaluated a Sixth Circuit decision holding a habeas petitioner’s sentencing instructions unconstitutional. The Supreme Court found the forms and instructions used in the sentencing phase of Spisak’s trial “differ[ed] significantly,”
Spisak,
[Y]ou, the trial jury, must consider all of the relevant evidence raised at trial, the evidence and testimony received in this hearing and the arguments of counsel. From this you must determine whether, beyond a reasonable doubt, the aggravating circumstances, which [Spisak] has been found guilty of committing in the separate counts are sufficient to outweigh the mitigating factors present in this case.
If all twelve members of the jury find by proof beyond a reasonable doubt that the aggravating circumstance in each separate count outweighs the mitigating factors, then you must return that finding to the Court.
On the other hand, if after considering all of the relevant evidence raised at trial, the evidence and the testimony received at this hearing and the arguments of counsel, you find that the State failed to prove beyond a reasonable doubt that the aggravating circumstances which [Spisak] has been found guilty of committing in the separate counts outweigh the mitigating factors, you will then proceed to determine which of two possible life imprisonment sentences to recommend to the Court.
Id. at 683-84 (alteration in original) (internal quotation marks omitted). Two sets of verdict forms were made available to the jury. One read:
We the jury in this case ... do find beyond a reasonable doubt that the aggravating circumstance which the defendant ... was found guilty of committing was sufficient to outweigh the mitigating factors present in this ease.
We the jury recommend that the sentence of death be imposed....
Spisak Trial Transcript of July 19,1983, at 2975-76, Court of Common Pleas, Cuyahoga County, Ohio. The other read:
We the jury ... do find that the aggravating circumstances which the defendant ... was found guilty of committing are not sufficient to outweigh the mitigating factors present in this case.
We the jury recommend that the defendant ... be sentenced to life imprisonment. ...
Id. at 2976.
After reviewing the jury instructions and the language of the verdict forms, the Supreme Court found that:
The instructions and forms made clear that, to recommend a death sentence, the jury had to find, unanimously and beyond a reasonable doubt, that each of the aggravating factors outweighed any mitigating circumstances. But the instructions did not say that the jury must determine the existence of each individual mitigating factor unanimously. Neither the instructions nor the forms said anything about how — or even whether— the jury should make individual determinations that each particular mitigating circumstance existed. They focused only on the overall balancing question. And the instructions repeatedly told the jury to “conside[r] all of the relevant evidence.”
Spisak,
In our view the instructions and verdict forms did not clearly bring about, either through what they said or what they implied, the circumstance that Mills found critical, namely, “a substantial possibility [sic] that reasonable jurors, upon receiving the judge’s instructions in this case, and in attempting to complete the verdict form as instructed, well may have thought they were precluded *379 from considering any mitigating evidence unless all 12 jurors agreed on the existence of a particular such circumstance.”
Id.
at 684 (quoting
Mills,
The Commonwealth claims the instructions examined in
Spisak
are “virtually identical” to the language at issue here, which must therefore also be read to address only the final balancing question. The Commonwealth sees equivalence in “ ‘[i]f all twelve members of the jury find by proof beyond a reasonable doubt that the aggravating circumstance in each separate count outweighs the mitigating factors,’ ”
Spisak,
We disagree. The identified language of unanimity at issue in
Spisak
addressed only how the jury should weigh aggravating and mitigating circumstances, not how to find either individual aggravating or mitigating circumstances.
Spisak,
The verdict form and judge’s instructions used in the sentencing phase of AbuJamal’s trial are materially different and easily distinguished from those at issue in
Spisak.
By contrast with
Spisak,
the identified language of unanimity here indisputably addresses more than the final balancing of aggravating and mitigating factors. “We, the jury, have found unanimously,” directly refers to “one or more aggravating circumstances,” and in the absence of any instruction or even suggestion to the contrary, it is substantially probable the jury applied the unanimity requirement to “mitigating circumstances” as well. When “read naturally,”
Spisak,
Moreover, by further contrast with Spisak, the form and instructions required the jury to make individual determinations that certain identified mitigating circumstances existed and “said or ... implied,” id. at 684, that these determinations must be made unanimously. The verdict form at issue in this case required the jury to select any mitigating circumstances found from a list of potentially mitigating circumstances; as discussed, the list is accompanied by spaces for a checkmark after each potential circumstance. The trial judge instructed the jury to identify each mitigating circumstance it found and considered in its weighing of aggravating and mitigating circumstances:
[The] mitigating circumstances appear on the third page here. They run from a little (a) to a little letter (h). And whichever ones you find there, you will put an “X” mark or check mark and then, put it on the front here at the bottom [of the first page], which says mitigating circumstances.
*380
In
Spisak
the jury had already determined the existence of aggravating circumstances at the guilt phase, separately from and before the sentencing phase of the trial. Here, the form and instructions required the jury to make individual determinations regarding both mitigating and aggravating circumstances contemporaneously during the penalty phase. The verdict form introduced the list of potential mitigating circumstances with the list of aggravating circumstances under one heading reading “AGGRAVATING AND MITIGATING CIRCUMSTANCES.” The jury was instructed identically as to each list.
8
The parallel structure of the form in relation to aggravating and mitigating circumstances reads that findings as to each should be made similarly.
See Mills,
Accordingly, we conclude our judgment that there is a “substantial probability” the jury believed it could not consider any mitigating circumstance not unanimously agreed upon is consistent with
Spisak.
“There is, of course, no extrinsic evidence
*381
of what the jury in this case actually thought.”
Mills,
V.
The Pennsylvania Supreme Court’s decision to reject Abu-Jamal’s mitigation instruction claim involved an objectively unreasonable application of Mills. On post-conviction review of this matter, the Pennsylvania Supreme Court found no Mills violation. The Court reasoned:
The verdict slip employed in the instant case consisted of three pages. The requirement of unanimity is found only at page one in the section wherein the jury is to indicate its sentence. The second page of the form lists all the statutorily enumerated aggravating circumstances and includes next to each such circumstance a designated space for the jury to mark those circumstances found. The section where the jury is to checkmark those mitigating circumstances found, appears at page three and includes no reference to a finding of unanimity. Indeed, there are no printed instructions whatsoever on either page two or page three. The mere fact that immediately following that section of verdict slip, the jurors were required to each sign their name is of no moment since those signature lines naturally appear at the conclusion of the form and have no explicit correlation to the checklist of mitigating circumstances. As such, we cannot conclude, as Appellant urges, that the structure of the form could lead the jurors to believe that they must unanimously agree on mitigating evidence before such could be considered. Moreover, verdict slips similar to that employed in the instant matter have been held by our court not to violate the dictates of Mills.
Commonwealth v. Abu-Jamal,
The Pennsylvania Supreme Court focused exclusively on the verdict form and reached its conclusion without considering the entire jury charge. Significantly, the court did not evaluate or address the trial judge’s oral instructions. See id. As a consequence, the court did not consider whether the language “a verdict must be a sentence of death ... if the jury unanimously finds one or more aggravating circumstances which outweigh any mitigating circumstances,” would create a substantial probability the jury had understood the instructions to preclude consideration of mitigating circumstances that were not agreed to by all twelve members of the jury. Nor did the court consider the effect on the jury of being instructed identically and contemporaneously with respect to the making of individual determinations regarding mitigating and aggravating circumstances. Moreover, although the court rejected the claim that the “structure of the form could lead the jurors to believe that they must unanimously agree on mitigating evidence before such could be considered,” id., it conducted an incomplete analysis of only a portion of the verdict form, rather than the entire form. The court did not consider whether the language “[w]e, the jury, have found unanimously ... one or more aggravating circumstances which outweigh any mitigating circumstances,” would create a substantial *382 probability the jury had applied the form in violation of Mills, nor did the court address the likely effect on the jury of having to choose aggravating and mitigating circumstances from visually identical lists and represent its findings as to each in an identical manner. Accordingly, the Pennsylvania Supreme Court failed to evaluate whether the complete text of the verdict form, together with the jury instructions, would create a substantial probability the jury believed both aggravating and mitigating circumstances must be found unanimously. See id. For these reasons, the Pennsylvania Supreme Court’s application of Mills was objectively unreasonable.
VI.
Like the
Mills
Court, “[although we are hesitant to infer too much about the ... verdict form from ... well-meant efforts to remove ambiguity from the State’s capital sentencing scheme, we cannot avoid noticing ... significant changes effected in instructions to the jury.”
II. SENTENCING VERDICT AND FINDINGS
If you have reached a unanimous verdict, complete this part of the form.
In Section A, indicate whether the sentencing verdict is death or life imprisonment. If the sentence is death, indicate the basis for that verdict by completing Section B. If the sentence is life imprisonment, indicate the basis for that verdict by completing Section C.
A. We, the jury, unanimously sentence the defendant to (check one): _Death
__ Life Imprisonment
B. The findings on which the sentence of death is based are (check one):
___ 1. At least one aggravating circumstance and no mitigating circumstance.
The aggravating circumstanee(s) unanimously found (is)(are):
_2. One or more aggravating circumstances which outweigh(s) any mitigating circumstance(s).
The aggravating circumstance(s) unanimously found (is)(are):
The mitigating circumstanee(s) found by one or more of us (is)(are):
C. The findings on which the sentence of life imprisonment is based are (check one):
_ 1. No aggravating circumstance exists.
_____ 2. The mitigating circumstance^) (is)(are) not outweighed by the aggravating circumstance(s).
The mitigating circumstance(s) found by one or more of us (is)(are):
The aggravating circumstance(s) unanimously found (is)(are):
*383 Pa. R. Crim. P. 358A (emphasis added). The form used in Abu-Jamal’s trial simply read “[w]e, the jury, have found unanimously ... one or more aggravating circumstances which outweigh any mitigating circumstances. The aggravating circumstance(s) is/are__The mitigating circumstanee(s) is/are__” By contrast, the revised uniform verdict slip states “[t]he mitigating circumstance(s) found by one or more of us (is) (are),” thereby making clear that, although aggravating circumstances must be found unanimously, mitigating evidence need not be found unanimously in order to be considered by individual jurors during the weighing and balancing process. The Pennsylvania Suggested Standard Criminal Jury Instructions were also amended to remove ambiguity with respect to the consideration of mitigating evidence during the weighing and balancing process. See Pennsylvania Suggested Standard Criminal Jury Instructions § 15.2502H(3) (2006). The new instruction reads, in relevant part:
When voting on the general findings, you are to regard a particular aggravating circumstance as present only if you all agree that it is present. On the other hand, each of you is free to regard a particular mitigating circumstance as present despite what other jurors may believe. This is different from the general findings to reach your ultimate sentence of either life in prison or death. The specific findings as to any particular aggravating circumstance must be unanimous. All of you must agree that the Commonwealth has proven it beyond a reasonable doubt. That is not true for any mitigating circumstance. Any circumstance that any juror considers to be mitigating may be considered by that juror in determining the proper sentence. This different treatment of aggravating and mitigating circumstances is one of the law’s safeguards against unjust death sentences. It gives a defendant the full benefit of any mitigating circumstances. It is closely related to the burden of proof requirements. Remember, the Commonwealth must prove any aggravating circumstance beyond a reasonable doubt while the defendant only has to prove any mitigating circumstance by a preponderance of the evidence. Your final sentence — life imprisonment or death — must be unanimous. All of you must agree that the sentence should be life imprisonment or that the sentence should be death because there is at least one aggravating circumstance and no mitigating circumstance or because the aggravating circumstance or circumstances outweigh the mitigating circumstance or circumstances found by any juror.
Id.
These clarifications highlight the ambiguity at issue in this case and on their own serve at least to suggest the substantial probability that “some jurors were prevented from considering ‘factors which may call for a less severe penalty.’ ”
Mills,
VII.
For the foregoing reasons, we will affirm the District Court’s grant of relief on the mitigation instruction claim. As the District Court noted, the “Commonwealth of Pennsylvania may conduct a new sentencing hearing in a manner consistent with this opinion within 180 days of the
*384
Order accompanying this [opinion], during which period the execution of the writ of habeas corpus will be stayed, or shall sentence [Abu-Jamal] to life imprisonment.”
Abu-Jamal,
Notes
. Abu-Jamal claimed the jury was unconstitutionally limited in its consideration of mitigating factors to only mitigating factors found unanimously by the jury.
See Mills v. Maryland,
. As noted, a divided panel affirmed the denial of habeas relief on the conviction; the entire panel affirmed the grant of habeas relief on the sentence.
See Abu-Jamal,
.
Spisak
used the word "possibility” instead of “probability” when quoting directly from
Mills. See
. In
Boyde v. California,
. The jury in
Mills
did not mark "yes” next to any mitigating circumstance,
. The jury placed a checkmark next to mitigating circumstance (a) on the third page and then indicated this selection on the first page by writing "A.” Circumstance (a) reads: “The defendant has no significant history of prior criminal convictions[.]” Circumstance (h) allowed the jury to consider and select “[a]ny other mitigating matter concerning the character or record of the defendant or the circumstances of his offense.”
. The same language appears again in the jury instructions: "The Crimes Code provides that a verdict must be a sentence of death ... if the jury unanimously finds one or more aggravating circumstances which outweigh any mitigating circumstances.”
. The jury instructions for aggravating circumstances stated:
And what you do, you go to Page 2. Page 2 lists all the aggravating circumstances. They go from small letter (a) to small letter (j). Whichever one of these that you find, you put an "X” or check mark there and then, put it on the front. Don’t spell it out, the whole thing, just what letter you might have found.
The trial judge reiterated this instruction for the "second block” under section (2) and then instructed the jury as to mitigating circumstances:
And then, you would as I said before, on the second page indicate which [aggravating circumstances] ,they were and put it on the front here, like a small number or (a) or (b) or (c) or whatever one you might find. And then, underneath that, there are: "The mitigating circumstances(s) [sic] is/are ._ And those mitigating circumstances appear on the third page here. They run from a little (a) to a little letter (h). And whichever ones you find there, you will put an "X” mark or check mark and then, put it on the front here at the bottom, which says mitigating circumstances.
. The jury instructions stated:
The [C]ommonwealth has the burden of proving aggravating circumstances beyond a reasonable doubt. The defendant has the burden of proving mitigating circumstances, but only by a preponderance of the evidence. This is a lesser burden of proof than beyond a reasonable doubt. A preponderance of the evidence exists where one side is more believable than the other side. All the evidence from both sides, including the evidence you heard earlier during the trial-in-chief as to aggravating or mitigating circumstances is important and proper for you to consider.
