*577MERRITT, J., delivered the opinion of the court, in which MOORE, J., joined. GILMAN, J. (pp. 598-616), delivered a separate dissenting opinion.
OPINION
MERRITT, Circuit Judge.We hold that the death sentence in this case violates the Eighth Amendment “arbitrariness” standard outlined in Furman v. Georgia, 408 U.S. 238, 92 S.Ct. 2726, 33 L.Ed.2d 346 (1972), which prohibits random, disproportionate capital sentences, as well as the proportionality requirement of Enmund v. Florida, 458 U.S. 782, 102 S.Ct. 3368, 73 L.Ed.2d 1140 (1982), and the due process, inconsistent verdict prohibition of Morrison v. California, 291 U.S. 82, 54 S.Ct. 281, 78 L.Ed. 664 (1934).
This is a contract murder case with irreconcilable jury verdicts leading one defendant to be sentenced to death and another — the defendant who initiated, contracted for, and paid for the murder — to be sentenced to life imprisonment. Pour defendants, Jason Getsy, Richard McNulty, Ben Hudach, and John Santine, were charged with committing the murder of Ann Serafíno and the attempted murder of Charles (“Chuekie”) Serafino “for hire.” Santine was charged with hiring the other three defendants to kill Chuekie Serafino, a business rival. Santine was sentenced to life imprisonment when a jury found him guilty of aggravated murder but not guilty of hiring Getsy to commit the murder. McNulty and Hudach were sentenced to life imprisonment after they were allowed to plead guilty. A jury found only nineteen-year-old Getsy guilty of the crime of murder for hire initiated by Santine and sentenced him to death. The Supreme Court of Ohio allowed Getsy’s death sentence to stand, but expressed its dismay about the disproportionate nature of these inconsistent results:
That Hudach received a lesser penalty than Getsy is not surprising — Hudach did not enter the Serafino home. McNulty did, and he shot one of the victims; nevertheless, he was offered a plea bargain, Getsy was not. Furthermore, McNulty did not testify against Getsy; therefore, McNulty’s case was not a case of the state’s needing to secure testimony to obtain a conviction on a more culpable person.
It is also troubling that Santine did not receive the death sentence even though he initiated the crime. If not for John Santine, it is unlikely the Serafinos would have been shot.
State v. Getsy, 84 Ohio St.3d 180, 702 N.E.2d 866, 892 (Ohio 1998). We agree with the Ohio Supreme Court’s suggestion that Santine is probably more — certainly no less — culpable than Getsy, the young boy he hired, but we do not agree that the death verdict can stand. As explained below, the death sentence violates Furman, Enmund, and Morrison because like crimes are not being punished alike in the very same case and because of the inconsistent jury verdicts in this case. We also remand the case to the district court for an evidentiary hearing on Getsy’s claim of judicial bias in his case.
I. Background
The facts of this case, set forth below, are excerpted from State v. Getsy, 84 Ohio St.3d 180, 702 N.E.2d 866, 873-75 (Ohio 1998):
Charles (“Chuekie”) Serafino lived with his mother, Ann Serafino. On the evening of July 6, 1995, Ann went to bed at approximately 11:00 p.m. Chuekie was on the love seat in the family • room when, sometime after 1:00 a.m. on July 7, he heard a loud explosion. Shells *578from a shotgun blasted out the sliding glass door behind him and wounded him in the arm. As he ran for the bathroom to inspect his injuries, Ann came out of her bedroom. Chuckie remembered hearing his mother say to someone, “What are you doing here? Get out of here.” He also remembered hearing someone say, “Shoot the bitch,” or “Kill the bitch.” Serafino next recalled seeing a gun in his face and being shot again. He fell to the bathroom floor and pretended to be dead. After the intruders left, he called 911....
Earlier in the year, [John] Santine had attempted to purchase a portion of Chuckie Serafino’s lawn-care business and had deposited $2,500 in the business's -account. Subsequently, Chuckie violated probation and was incarcerated in the Trumbull County Jail until July 6, 1995. While Chuckie was in jail, San-tine attempted to take over Chuckie’s business. Santine transferred Chuckie’s building lease and equipment into his own name, which caused an altercation between Santine and Ann Serafino and Chuckie’s sister. The Serafinos filed a civil action against Santine while Chuck-ie was still in jail.
[After the shootings, Officer] Forgacs [of the city of Hubbard Police Department] searched for Santine’s car because of a conversation he had had on June 20, 1995 with Richard McNulty. McNulty, who lived at 24% South Main and who is a codefendant, had previously served as a police informant. On June 20, For-gacs asked McNulty, who worked for Santine, “What does Johnny have in store for Chuckie when he gets out of jail?” McNulty told Forgacs, “He’s dead. He’s bought and paid ■ for.” McNulty told Forgacs that Santine had lined up a hit man, Tony Antone, to kill Chuckie Serafino. Forgacs gave little credence to McNulty’s statements, and didn’t inform Chuckie or follow up on the information....
Initially, McNulty minimized his involvement and denied that he had told For-gacs about the contract on Chuckie. Based on other information obtained from McNulty, Begeot obtained an arrest warrant for Getsy. At approximately 10:00 p.m. on July 7, 1995, Getsy was arrested in the driveway of 24% South Main. He was given Miranda warnings at the scene and later at the Hubbard Township Police Department. At approximately 1:00 a.m., on July 8, 1995, Getsy gave a' videotaped interview. Getsy told Begeot that Ben Hudach called him on the evening of July 6, 1995, and told him to come to 24% South Main Street. When Getsy got there, Hudach, a codefendant, told Getsy that they (Getsy, Hudach, and McNulty) had to “take out some guy.” Santine was not present, but Hudach related what Santine had told him earlier. Money had been discussed, but Hudach was not sure of the amount. Getsy later indicated that he participated in the shootings because he was scared of Santine, but did not do it for the money.
Sometime on July 6, 1995, Getsy, Hu-dach, and McNulty drove to the Serafino residence. They could not find a place to park so they returned to 24% South Main Street. When they returned, San-tine was at the apartment and drove them back to the Serafino house. Getsy described the guns that they took with them, which included a shotgun, a SKS rifle, and a .357 magnum handgun.
Getsy explained that after Santine dropped them off, Hudach sprained his ankle and went back to where they were supposed to be picked up. Getsy stated, “[T]hat left me and Rick to get it done.” He admitted that what they were supposed to do was kill Chuckie Serafino. *579Getsy explained that he and McNulty fired simultaneously through the sliding glass door on the back of the Serafino house. They entered the house through the shattered door and shot at Chuekie as he was running down the hall. When they saw Ann Serafino, Getsy stated, they “just kept shooting.”
During the interview with Begeot, Getsy was reluctant to mention Santine’s name. He told Begeot that the same thing that happened last night could happen to him. He asked whether San-tine would ever see the interview tape. Begeot assured Getsy that Santine would not be able to get to him. Getsy also asked Begeot if he was going to die, and Begeot told him, “No.”
Getsy admitted that he had the SKS rifle and the handgun during the shootings. He explained that when he was shooting the SKS, the clip fell out so he had to pull out the handgun----
After the shootings, Hudach called San-tine to tell him it was finished and to pick them up. Santine told Hudach that there were cops everywhere and that they should run through the woods to get back to the apartment. Santine also told Hudach to ditch the guns in the woods.
Getsy, McNulty, and Hudach arrived back at 24$ South Main, where Josh Koch and Santine were waiting for them. Santine ordered them to take off their clothes and take a bath. Getsy was the last to bathe. When he came out of the bathroom, his clothes and boots were gone. He did not know what happened to them. •
Koch testified that he was at 24$ South Main Street on July 6 and 7, 1995. He knew that Getsy, McNulty, and Hudach were going out to do something for San-tine, but they declined to give him any details. He was to watch TV and write down the shows that were on so the other three could memorize the list for an alibi.
After Getsy, McNulty, and Hudach left, Koch waited in the apartment. Santine came to the apartment and, sometime around 1:00 a.m., jumped up and said, “I heard the gunshots.” Immediately thereafter, the telephone rang and Koch heard Santine talking to someone in a fast, excited manner. Santine said, “So you killed them, right, you killed them both? ... Okay. Well, I can’t come pick you up. The cops are everywhere, they are pulling over everybody, you got to run through the woods and ditch the guns.” Santine hung up and happily screamed, “I fucking love these guys.” According to Koch, Santine was very pleased with the three men. He said, “You guys want $10,000? I’ll give you $10,000.” McNulty told him he just wanted a wedding ring for his girlfriend. Hudach said that it had been a favor for Santine. Getsy indicated that he needed money for his car.
The next day, Koch heard Getsy bragging to Patricia Lawson about shooting Ann Serafino. Getsy grabbed a piece of pizza with no cheese on it and said, “This looks just like this bitch’s face after we shot her.”
Based on these facts, the Trumbull County Grand Jury returned a five-count indictment against Getsy on July 17, 1995. The indictment charged Getsy with the aggravated murder of Ann Serafino with prior calculation and design in violation of Ohio Rev.Code Ann. § 2903.01(A). That count included three death penalty specifications: (1) the aggravated murder was committed in conjunction with the purposeful killing of or attempt to kill two or more persons, Ohio Rev.Code Ann. § 2929.04(A)(5); (2) murder for hire, Ohio Rev.Code Ann. § 2929.04(A)(2); and (3) *580felony murder, Ohio Rev.Code Ann. § 2929.04(A)(7). On August 5, 1996, Getsy proceeded to a jury trial before the Trumbull County Court of Common Pleas. The jury returned verdicts finding Getsy guilty on all counts and specifications; thereafter, the prosecution dismissed the conspiracy count. Following a mitigation hearing under Ohio Rev.Code Ann. §§ 2929.022(A), 2929.03, and on September 10, 1996, the jury recommended that the death penalty be imposed on Getsy. Two days later, the trial court accepted the jury’s recommendation and imposed a death sentence for the charge of aggravated murder. The defendant appealed to the Ohio Supreme Court, which affirmed his conviction and sentence. State v. Getsy, 84 Ohio St.3d 180, 702 N.E.2d 866, 893 (Ohio 1998).
Getsy filed a petition pursuant to 28 U.S.C. § 2254 in February 2001 after exhausting his state remedies. Getsy raised twenty-one claims of error, two of which the district court dismissed as procedurally defaulted. The district court determined that Getsy’s remaining claims were without merit and dismissed the petition. Get-sy now appeals from the district court’s order dismissing his habeas corpus petition.
II. Standard of Review
In determining whether to issue a writ of habeas corpus, the provisions of the Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA) govern our review of a state court judgment. 28 U.S.C. § 2241, amended by Pub.L. No. 109-163, § 373, 119 Stat. 3136 (2006). Pursuant to AED-PA, an Article III court can grant the writ of habeas corpus where the state court judgment was “contrary to, or 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).
The Supreme Court has defined “clearly established law” as “the holdings, as opposed to the dicta, of [the Supreme Court’s] decisions as of the time of the relevant state-court decision.” (Terry) Williams v. Taylor, 529 U.S. 362, 412, 120 S.Ct. 1495, 146 L.Ed.2d 389 (2000). For purposes of § 2254(d)(1), an explicit statement of a particular rule by the Supreme Court is not necessary; rather, “[t]he Court has made clear that its relevant precedents include not only bright-line rules but also the legal principles and standards flowing from precedent.” Ruimveld v. Birkett, 404 F.3d 1006, 1010 (6th Cir.2005) (quoting Taylor v. Withrow, 288 F.3d 846, 852 (6th Cir.2002)). A state court decision is “contrary to” clearly established Supreme Court precedent “if the state court applies a rule that contradicts the governing law set forth in [the Supreme Court’s] cases” or “if the state court confronts a set of facts that are materially indistinguishable from a decision of [the Supreme] Court and nevertheless arrives at a result different from [its] precedent.” (Terry) Williams, 529 U.S. at 405-06, 120 S.Ct. 1495. A state court decision is an “unreasonable application of’ clearly established Federal law “if the state court identifies the correct governing legal rule from [the Supreme Court’s] cases but unreasonably applies it to the facts of the particular state prisoner’s case.” Id. at 407, 120 S.Ct. 1495.
The Supreme Court has adopted the spectrum of abstraction of Teague v. Lane, 489 U.S. 288, 109 S.Ct. 1060, 103 L.Ed.2d 334 (1989), to determine whether a particular legal principle was clearly established at the relevant time. See (Teiry) Williams, 529 U.S. at 412, 120 S.Ct. 1495 (With the caveat that the source of clearly established law is Supreme Court jurisprudence, “whatever would qualify as an old rule under our Teague jurisprudence will *581constitute ‘clearly established Federal law, as determined by the Supreme Court of the United States’ under § 2254(d)(1).”). At one end of the spectrum lie legal principles with such a high level of generality that their application does not necessarily lead to a “predictable development” in the relevant law and therefore cannot be considered clearly established. See Sawyer v. Smith, 497 U.S. 227, 236, 110 S.Ct. 2822, 111 L.Ed.2d 193 (1990). On the other end are narrowly drawn bright-line rules with little application beyond factually indistinguishable eases. In the middle of the spectrum lie those general principles of law crafted by the Supreme Court to constitute clearly established law in a wide range of factual situations. It was the middle of the spectrum that Justice Kennedy described while concurring in Wright v. West, 505 U.S. 277, 308-09, 112 S.Ct. 2482, 120 L.Ed.2d 225 (1992):
If the rule in question is one which of necessity requires a case-by-case examination of the evidence, then we can tolerate a number of specific applications without saying that those applications themselves create a new rule .... Where the beginning point is a rule of this general application, a rule designed for the specific purpose of evaluating a myriad of factual contexts, it will be the infrequent case that yields a result so novel that it forges a new rule, one not dictated by precedent.
A majority of the Supreme Court has adopted Justice Kennedy’s “case-by-case” approach. See (Terry) Williams, 529 U.S. at 391, 120 S.Ct. 1495 (“That the Strickland test ‘of necessity requires a case-by-case examination of the evidence’ obviates neither the clarity of the rule nor the extent to which the rule must be seen as ‘established’ by this Court.”) (citations omitted); Rompilla v. Beard, 545 U.S. 374, 125 S.Ct. 2456, 2471, 162 L.Ed.2d 360 (2005) (O’Connor, J., concurring) (noting the “ ‘case-by-case examination of the evidence’ called for under our cases”); (Terry) Williams, 529 U.S. at 382, 120 S.Ct. 1495 (Stevens, J., dissenting in part) (“In the context of this case, we also note that, as our precedent interpreting Teague has demonstrated, rules of law may be sufficiently clear for habeas purposes even when they are expressed in terms of a generalized standard rather than as a bright-line rule.”).
The Furman arbitrariness principle, as supplemented by the rules against disproportionate sentences and irreconcilable jury verdicts in the same case (discussed below), falls well within the middle of Teague’s spectrum of abstraction, in that these principles provide sufficient content for predictable legal development and apply to a range of factual situations. See Gregg v. Georgia, 428 U.S. 153, 195, 96 S.Ct. 2909, 49 L.Ed.2d 859 (1976) (noting that “each distinct [sentencing] system must be examined on an individual basis” to determine if it satisfies the concerns of Furman). The Furman principle of general application interpreting the Eighth Amendment has been clearly established since 1972, decades before the state judgment at issue here. Moreover, the arbitrariness principle clearly applies here because the inconsistent verdicts and the resulting disproportionate sentences in this case are exactly the sort of unconstitutionally arbitrary and capricious outcomes that Furman and its progeny condemned.
III. Constitutionality of Death Sentence
Getsy contends that his sentence of death was imposed in an arbitrary and capricious manner in violation of the Eighth Amendment of the United States Constitution because Santine, who initiated, contracted for, and paid for the mur*582der, was acquitted of murder for hire and sentenced to life imprisonment. Relying on Furman v. Georgia, 408 U.S. 238, 92 S.Ct. 2726, 33 L.Ed.2d 346 (1972), Getsy claims that the Ohio Supreme Court’s rejection of his Eighth Amendment argument was “contrary to” relevant Supreme Court precedent. We hold that the “arbitrariness” principle firmly established in Furman and its progeny would be offended if the irreconcilable, arbitrary jury verdicts in this case were allowed to stand. We, therefore, conclude that Getsy’s death sentence must be vacated.
A. Furman Principles
The Supreme Court has clearly established that the Cruel and Unusual Punishments Clause of the Eighth Amendment condemns “the arbitrary infliction” of the death penalty. Furman, 408 U.S. at 274, 92 S.Ct. 2726 (Brennan, J., concurring). In Furman v. Georgia, the Supreme Court, in a one paragraph per curiam opinion, held that the death penalty, as then administered under statutes vesting unguided sentencing discretion in juries and trial judges, was unconstitutionally cruel and unusual punishment in violation of the Eighth and Fourteenth Amendments. Id. at 239-40, 92 S.Ct. 2726. The concurring opinions that followed explained that the death penalty was being imposed so dis-criminatorily, id. at 240, 92 S.Ct. 2726 (Douglas, J., concurring), so wantonly and freakishly, id. at 306, 92 S.Ct. 2726 (Stewart, J., concurring), and so infrequently, id. at 310, 92 S.Ct. 2726 (White, J., concurring), that any given death sentence was unconstitutionally cruel and unusual. Justice White concluded that “the death penalty is exacted with great infrequency even for the most atrocious crimes and that there is no meaningful basis for distinguishing the few cases in which [the death penalty] is imposed from the many cases in which it is not.” Id. at 313, 92 S.Ct. 2726 (concurring). Indeed, the death sentences examined by the Supreme Court in Fur-man were “cruel and unusual in the same way that being struck by lightning is cruel and unusual. For, of all the people convicted of [capital crimes], many just as reprehensible as these, the petitioners [in Furman were] among a capriciously selected random handful upon whom the sentence of death ha[d] in fact been imposed.” Id. at 309-10, 92 S.Ct. 2726 (Stewart, J., concurring). Thus, Furman established that the Eighth and Fourteenth Amendments cannot tolerate the infliction of a sentence of death under legal systems that permit this penalty to be arbitrarily and capriciously imposed. See id. at 310, 92 S.Ct. 2726; Spaziano v. Florida, 468 U.S. 447, 460, 104 S.Ct. 3154, 82 L.Ed.2d 340 (1984) (Furman established that “[i]f a State has determined that death should be an available penalty for certain crimes, then it must administer that penalty in a way that can rationally distinguish between those individuals for whom death is an appropriate sanction and those for whom it is not.”); Godfrey v. Georgia, 446 U.S. 420, 428, 100 S.Ct. 1759, 64 L.Ed.2d 398 (1980) (Furman established that “if a State wishes to authorize capital punishment it has a constitutional responsibility to ... apply its law in a manner that avoids the arbitrary and capricious infliction of the death penalty.”).
As it has evolved since Furman, the Eighth Amendment arbitrariness standard generally prohibits the infliction of a death sentence discriminatorily on the basis of illegitimate and suspect factors, such as the race or socioeconomic status of the defendant and the victim, and its inconsistent or random imposition. See Eddings v. Oklahoma, 455 U.S. 104, 111, 102 S.Ct. 869, 71 L.Ed.2d 1 (1982) (Beginning with Furman, the Court has emphasized its pursuit of the “goals of *583measured, consistent application and fairness to the accused.”); David C. Baldus et al., Arbitrariness and Discrimination in the Administration of the Death Penalty: A Legal and Empirical Analysis of the Nebraska Experience (1973-1999), 81 Neb. L.Rev. 486, 496 (2002). The second source of arbitrariness, inconsistent and unprincipled outcomes, constituted a major factual foundation of the Furman holding. See Baldus et al., supra, at 496 n. 5. The Furman Court invalidated existing death penalty laws because, as the laws were structured and administered at the time, they failed to generate acceptably consistent outcomes. See Furman, 408 U.S. at 295, 92 S.Ct. 2726 (Brennan, J., concurring) (noting that the existing procedures were not constructed to guard against the totally arbitrary selection of offenders for the punishment of death); Blystone v. Pennsylvania, 494 U.S. 299, 303, 110 S.Ct. 1078, 108 L.Ed.2d 255 (1990) (noting that the constitutional defect identified in Furman was that “unguided juries were imposing the death penalty in an inconsistent and random manner on defendants”). Each of the concurring opinions in Furman relied upon various forms of statistical evidence that purported to demonstrate patterns of inconsistent or otherwise arbitrary sentencing. Furman, 408 U.S. at 249-52, 92 S.Ct. 2726 (Douglas, J., concurring); id. at 291-95, 92 S.Ct. 2726 (Brennan, J., concurring); id. at 309-10, 92 S.Ct. 2726 (Stewart, J., concurring); id. at 313, 92 S.Ct. 2726 (White, J., concurring); id. at 364-66, 92 S.Ct. 2726 (Marshall, J., concurring). Evidence of such inconsistent results, of sentencing decisions that could not be explained on the basis of individual culpability, indicated that the system operated arbitrarily and therefore violated the Eighth Amendment.
The Supreme Court has affirmed this conception of the Eighth Amendment in its decisions following Furman. Thus, the Court has insisted that “capital punishment be imposed fairly, and with reasonable consistency, or not at all.” Eddings, 455 U.S. at 112, 102 S.Ct. 869. To satisfy the concerns of Furman, the Supreme Court has thereafter required that the sentencing body’s discretion be “directed and limited” and exercised in an “informed manner” to avoid “wholly arbitrary and capricious action.” Gregg v. Georgia, 428 U.S. 153, 189, 96 S.Ct. 2909, 49 L.Ed.2d 859 (1976). Furman was read as holding that “to minimize the risk that the death penalty [will] be imposed on a capriciously selected group of offenders, the decision to impose it ha[s] to be guided by standards so that the sentencing authority [will] focus on the particularized circumstances of the crime and the defendant.” Id. at 199, 96 S.Ct. 2909. The jury should be “given guidance regarding the factors about the crime and the defendant that the State, representing organized society, deems particularly relevant to the sentencing decision.” Id. at 192, 96 S.Ct. 2909. “Otherwise, the system cannot function in a consistent and a rational manner.” Id. at 189, 96 S.Ct. 2909.
It is now well settled that “the penalty of death is different in kind from any other punishment imposed under our system of justice.” Id. at 188, 96 S.Ct. 2909. “From the point of view of the defendant, it is different both in its severity and its finality. From the point of view of society, the action of the sovereign in taking the life of one of its citizens also differs dramatically from any other legitimate state action.” Gardner v. Florida, 430 U.S. 349, 357, 97 S.Ct. 1197, 51 L.Ed.2d 393 (1977). The qualitative difference of death from all other punishments requires a correspondingly greater need for reliability, consistency, and fairness in capital sentencing decisions. See, e.g., Ford v. Wainwright, 477 *584U.S. 399, 411, 106 S.Ct. 2595, 91 L.Ed.2d 335 (1986); Spaziano, 468 U.S. at 460 n. 7, 104 S.Ct. 3154; California v. Ramos, 463 U.S. 992, 998-99, 103 S.Ct. 3446, 77 L.Ed.2d 1171 (1983); Zant v. Stephens, 462 U.S. 862, 884-85, 103 S.Ct. 2733, 77 L.Ed.2d 235 (1983); Woodson v. North Carolina, 428 U.S. 280, 305, 96 S.Ct. 2978, 49 L.Ed.2d 944 (1976). It is of vital importance to the defendant and to the community that any decision to impose the death sentence be, and appear to be, based on reason rather than caprice or emotion. Gardner, 430 U.S. at 357, 97 S.Ct. 1197. Accordingly, the courts must “carefully scrutinize” sentencing decisions “to minimize the risk that the penalty -will be imposed in error or in an arbitrary and capricious manner. There must be a valid penological reason for choosing from among the many criminal defendants the few who are sentenced to death.” Spaziano, 468 U.S. at 460 n. 7, 104 S.Ct. 3154. The death-is-different principle can only be observed here by holding that the inconsistent and disproportionate sentences in the same case violate the clearly established Furman arbitrariness principle and hence the Eighth Amendment.
B. Disproportionality
Proportionality in sentencing is a major, independent element under the Eighth Amendment in assessing a death sentence. The comparative disproportionality between the culpability and sentences of Get-sy and Santine demonstrates the arbitrariness of Getsy’s death sentence. Unlike our later discussion of inconsistent verdicts, which focuses on the inconsistency of only one codefendant being found guilty of murder for hire, a crime necessarily requiring at least two participants, this disproportionality problem was noted by the Ohio Supreme Court because Getsy had arguably less culpability than Santine, but received a harsher sentence, the death penalty, rather than Santine’s life sentence:
It is clear that Getsy would not have committed these crimes if he had never met Santine ....
Santine was approximately thirty-five years old. Getsy was nineteen when the crimes were committed. Santine paid the rent for the apartment where Hu-dach and McNulty lived and supplied some of the drugs that they and their friends used. Santine bragged that he had connections with the mob and often spoke of his Mafia connections. When anyone in the group needed money, they asked Santine for it.
Santine bragged that he had the police in his pocket----Santine was known to have shot his own brother and apparently had never served time for the incident. Santine was known to routinely carry a duffel bag containing a gun. One time, Hudach and Robert Stonebur-ner were sitting with Santine when San-tine shot a wall for no apparent reason. Santine commented that he wished it had been Chuckie (Serafino) ....
It was clear from the videotape of his statement that Getsy feared Santine and was afraid that Santine would execute him. Getsy apparently was afraid to go to the police because Santine made it appear that he had the police in his pocket. This belief was supported by the fact that McNulty told police what Santine was planning and the police did nothing ....
When the group first went to the Serafi-no house, they returned to the apartment without completing the act, using the excuse that they could not find a place to park. Santine became furious, eventually driving Getsy, McNulty, and Hudach back to the place himself ....
*585It is also troubling that Santine did not receive the death sentence even though he initiated the crime. If not for John Santine, it is unlikely the Serafínos would have been shot.
State v. Getsy, 84 Ohio St.3d 180, 702 N.E.2d 866, 890-92 (Ohio 1998).
In evaluating whether a death sentence is arbitrary, the Supreme Court has directed courts to evaluate a defendant’s culpability both individually and in terms of the sentences of codefendants and accomplices in the same case. See Enmund v. Florida, 458 U.S. 782, 788, 798, 102 S.Ct. 3368, 73 L.Ed.2d 1140 (1982). In Enmund, the Supreme Court found the Eighth Amendment violated when defendants with “plainly different” culpability received the same capital sentence. It requires proportionality comparison with others participating in the same crime:
Enmund did not kill or intend to kill and thus his culpability is plainly different from that of the robbers who killed; yet the State treated them alike and attributed to Enmund the culpability of those who killed the Kerseys. This was impermissible under the Eighth Amendment.
Id. at 798, 102 S.Ct. 3368.
The instant case presents the reverse situation where defendants with plainly similar culpability received different sentences; and, furthermore, the defendant with arguably the lesser culpability received the harsher sentence — the death penalty. Numerous state courts have applied the Enmund principal to require reasonable symmetry between culpability and the sentencing of eodefendants. See, e.g., People v. Kliner, 185 Ill.2d 81, 235 Ill.Dec. 667, 705 N.E.2d 850, 897 (Ill.1998) (“[Similarly situated codefendants should not be given arbitrarily or unreasonably disparate sentences.”); Larzelere v. State, 676 So.2d 394, 406 (Fla.1996) (“When a codefendant ... is equally as culpable or more culpable than the defendant, disparate treatment of the codefendant may render the defendant’s punishment disproportionate.”); Hall v. State, 241 Ga. 252, 244 S.E.2d 833, 839 (Ga.1978) (‘We find that ... the death sentence, imposed on Hall for the same crime in which the co-defendant trigger-man received a life sentence, is disproportionate.”). Similarly, the Federal Death Penalty Act recognizes that a comparison of the sentences received by equally culpable codefendants improves the likelihood that the death penalty will not be imposed in an arbitrary or capricious manner. See 18 U.S.C. § 3592(a)(4) (listing as a mitigating factor the lack of death sentences for equally or more culpable codefendants).
The principle requiring proportionate punishment has deep roots in our cultural and biological heritage. Aristotle observed in his Nicomachean Ethics almost 2,500 years ago that basic notions of justice require treating like cases alike:
If, then, the unjust is unequal, the just is equal, as all men suppose it to be, even apart from argument .... This, then, is what the just is — the proportional; the unjust is what violates the proportion .... [I]t is by proportionate requital that the city holds together.
Aristotle, Ethica Nicomachea, in The Works of Aristotle V.3.1131a-1131b, V.5.1132b (W.D. Ross ed. & trans., 1954); see also Aristotle, The Politics of Aristotle 129 (Ernest Barker ed. & trans., 1946) (“Justice is the political good. It involves equality, or the distribution of equal amounts to equal persons.”).1 Recent *586studies have reinforced this view. In a recent article, Judge Morris Hoffman and Timothy Goldsmith, a distinguished Yale biologist, make this point:
[I]t is not surprising that collectively we struggle to balance the form and amount of punishment that is appropriate, a struggle that lies at the heart of what we mean by “justice.” ...
The two faces of justice' — to deal firmly with transgressors, but not too harshly — reflect an intrinsic human sense of fairness and are important to the political ideal of equality. When Aristotle commands that like cases be treated alike, he is touching both on the personal notion that none of us wants to be punished more than anyone else (and therefore on our self-interest) and on the social notion that none of us wants to punish others more than they deserve (and therefore on the equilibrium between our inclination to punish and our intuitions about fairness and sympathy). When sentencing guidelines address the tension between sentencing individual defendants and coordinating the sentences of similarly situated defendants, they are touching on this very same duality.
Morris B. Hoffman & Timothy H. Goldsmith, The Biological Roots of Punishment, 1 Ohio St. J.Crim. L. 627, 638-39 (2004). Coordination of sentences for the same crime is not simply a rational, legal principal but a deeply-held concept of justice as well.
The dissent argues incorrectly that the Supreme Court’s decision in Pulley v. Harris, 465 U.S. 37, 104 S.Ct. 871, 79 L.Ed.2d 29 (1984), precludes our consideration of the “comparative proportionality” of sentences in this case.2 Pulley simply held that the Eighth Amendment does not require a systematic comparative proportionality review of sentences in other unrelated cases. Id. at 50-51, 104 S.Ct. 871. Pulley concerned whether the Eighth Amendment mandates a systematic comparative proportionality review of a particular sentence to the punishment imposed on others for the same general type of crime but in unrelated cases. Our holding neither contradicts this rule nor implicates systematic comparative proportionality review. Cf. People v. Bean, 137 Ill.2d 65, 147 Ill.Dec. 891, 560 N.E.2d 258, 290 (Ill.1990) (“[I]n reviewing the appropriateness of a death sentence, this court will examine the facts of that particular case and the evi*587dence introduced at the trial and death penalty hearing, and, as a matter of reference, it may consider the sentence imposed on an accomplice or a co-defendant in light of his involvement in the offense.”). Instead, we simply adhere to the clearly established principle of Enmund that, in a capital case with respect to the very same crime stemming from the very same facts, the Eighth Amendment does not permit codefendants with plainly similar culpability to receive different sentences — especially when the defendant with arguably less culpability receives the harshest of all sentences, the death penalty. Following the dissent’s view would not only conflict with the clear mandate of Enmund but would allow less culpable participants in the same criminal episode to receive the death penalty when the more culpable participant receives a lesser sentence.
In sum, sentencing Getsy to death, while the arguably more culpable Santine received a life sentence for the very same crime, violates the Eighth Amendment, as construed by the Supreme Court in Fur-man and Enmund, and its prohibition of arbitrary and disproportionate death sentences.
C. Inconsistent Verdicts
The Supreme Court has declared that inconsistent verdicts are both scandalous and inequitable, Richardson v. Marsh, 481 U.S. 200, 210, 107 S.Ct. 1702, 95 L.Ed.2d 176 (1987), and has accordingly indicated that inconsistent verdicts “constitute evidence of arbitrariness that would undermine confidence in the quality of the [jury’s] conclusion,” Harris v. Rivera, 454 U.S. 339, 346, 102 S.Ct. 460, 70 L.Ed.2d 530 (1981). In concluding that the inconsistent jury verdicts in this case evidences that Getsy’s death sentence violates the Eighth Amendment arbitrariness principle outlined in Furman, we are informed by the common law rule of consistency, which was applied by the Supreme Court in Morrison v. California, 291 U.S. 82, 54 S.Ct. 281, 78 L.Ed. 664 (1934), and Hartzel v. United States, 322 U.S. 680, 64 S.Ct. 1233, 88 L.Ed. 1534 (1944). The common law rule of consistency prohibited a jury’s acquittal of all but one of multiple defendants charged with jointly committing a crime that requires at least two participants. E.g., Iannelli v. United States, 420 U.S. 770, 782, 95 S.Ct. 1284, 43 L.Ed.2d 616 (1975) (listing conspiracy, adultery, incest, bigamy, and dueling as offenses that require the participation of two people); Dunn v. United States, 284 U.S. 390, 402, 52 S.Ct. 189, 76 L.Ed. 356 (1932) (Butler, J., dissenting) (“Upon the indictment of several for an offense that could not be committed without the participation of two or more of them a verdict of guilty against one and of not guilty for the others, is deemed wholly repugnant and invalid.”).
The principle against inconsistent verdicts was well established at common law when we adopted the Eighth Amendment. Harison v. Errington, 79 Eng. Rep. 1292 (K.B.1627) (riot); Marsh v. Vauhan, 78 Eng. Rep. 937 (Q.B.1599) (conspiracy).3 The common law crime of riot provides a *588good example: “Under English law, that crime required three participants. It was legally impossible for fewer than three people to riot. Thus, if three defendants stood trial together for riot, and the jury convicted only one of them, this was a fatally inconsistent verdict, and the conviction could not stand.” Eric L. Muller, The Hobgoblin of Little Minds? Our Foolish Law of Inconsistent Verdicts, 111 Harv. L.Rev. 771, 779 (1998) (citing Hanson, 79 Eng. Rep. at 1293). “The argument was that as in conspiracy, if one only of two is found guilty the verdict is void ‘for one alone cannot conspire.’ ” Dir. Pub. Prosecutions v. Shannon, [1975] A.C. 717, 723 (discussing Harison).
At common law, the rule of consistency was frequently applied to address inconsistent verdicts between two codefendants charged with conspiracy. The crime of conspiracy cannot be committed by an individual acting alone since, by definition, conspiracy requires an agreement between two or more people to commit some unlawful act. Morrison, 291 U.S. at 92, 54 S.Ct. 281. Thus, the rule of consistency invalidates the conviction of one conspirator when all the other alleged conspirators are acquitted of the conspiracy charge.4 See, *589e.g., United States v. Crayton, 357 F.3d 560, 564 (6th Cir.2004); United States v. Espinosctr-Cerpa, 630 F.2d 328, 331 (5th Cir.1980); Developments in the Law— Criminal Conspiracy, 72 Harv. L.Rev. 922, 972-73 (1959). The basis for the rule of consistency in conspiracy cases “is the notion that the acquittal of all but one potential conspirator negates the possibility of an agreement between the sole remaining defendant and one of those acquitted of the conspiracy and thereby denies, by definition, the existence of any conspiracy at all.” Espinosa-Cerpa, 630 F.2d at 331. Under this reasoning, the conspiracy conviction of a lone defendant is invalid because “the verdict ... itself den[ies] the existence of the essential facts.” United States v. Austin-Bagley Corp., 31 F.2d 229, 233 (2d Cir.1929).
The Supreme Court has on at least two occasions applied the rule of consistency to set aside irreconcilable jury verdicts. In Morrison v. California, the Supreme Court held that the reversal of the conspiracy conviction of the defendant’s sole alleged co-conspirator on constitutional grounds required reversal of the defendant’s state conspiracy conviction. 291 U.S. at 93, 54 S.Ct. 281. In so holding, the Court stated:
It is impossible in the nature of things for a man to conspire with himself. In California as elsewhere conspiracy imports a corrupt agreement between not less than two with guilty knowledge on the part of each .... The conviction failing as to the one defendant must fail as to the other.
Id. at 92-93, 54 S.Ct. 281 (citations omitted); see also Gebardi v. United States, 287 U.S. 112, 123, 53 S.Ct. 35, 77 L.Ed. 206 (1932) (reversing defendant’s conviction of conspiracy to violate the Mann Act because his alleged co-conspirator was acquitted, and there was therefore “no proof that the man conspired with anyone else to bring about the transportation”). The Court went on to base its conclusion on the requirements of due process:
[T]he conviction of Morrison because he failed to assume the burden of disproving a conspiracy was a denial of due process that vitiates the judgment as to him. Nor is that the only consequence. Doi was not a conspirator, however guilty his own state of mind, unless Morrison had shared in the guilty knowledge and design.... The conviction failing as to the one defendant must fail as to the other.
Morrison, 291 U.S. at 93, 54 S.Ct. 281 (citing Turinetti v. United States, 2 F.2d 15 (8th Cir.1924)). In Turinetti v. United States, on which the Court relied, the court of appeals held that the release of one party to the agreement must lead to the acquittal of the second party:
Therefore, since Turinetti could not have conspired with himself alone, he could not under the law be convicted of a conspiracy. It follows that there is no lawful way to avoid a reversal also as to Turinetti, although, under the evidence, *590he violated one or more provisions of the National Prohibition Act. For the latter violations, however, he was neither indicted nor convicted, and so the fact of such other violations will not warrant affirmance of this conviction for conspiracy.
2 F.2d at 17.
Similarly, in Hartzel v. United States, 322 U.S. 680, 64 S.Ct. 1233, 88 L.Ed. 1534 (1944), the Supreme Court reversed a conspiracy conviction on the basis of inconsistency. Hartzel and two others were charged with violating and with conspiracy to violate the Espionage Act of 1917. The trial judge found the evidence insufficient to support the convictions of Hartzel’s two alleged co-conspirators. Id. at 682 n. 3, 64 S.Ct. 1233. The Supreme Court concluded that the setting aside of HartzePs only two co-conspirators’ convictions “makes it impossible to sustain petitioner’s conviction” for conspiracy to violate the Espionage Act. Id. Thus, Morrison and Hartzel now stand for the proposition that inconsistent or repugnant jury verdicts in conspiracy and other cases based on a criminal agreement between two parties cannot stand. This rule adds clarity, detail, and content to the more generalized “arbitrariness” language of Furman and mandates that Getsy’s death sentence be vacated.
Although several courts of appeals have questioned whether United States v. Powell, 469 U.S. 57, 105 S.Ct. 471, 83 L.Ed.2d 461 (1984), overruled the rule of consistency, see Crayton, 357 F.3d at 564; United States v. Acosta, 17 F.3d 538, 545-46 (2d Cir.1994); United States v. Zuniga-Salinas, 952 F.2d 876, 877-78 (5th Cir.1992) (en banc); United States v. Bucuvalas, 909 F.2d 593, 594-97 (1st Cir.1990); United States v. Thomas, 900 F.2d 37, 40 (4th Cir.1990); United States v. Dakins, 872 F.2d 1061, 1065-66 (D.C.Cir.1989); United States v. Mancari, 875 F.2d 103, 104 (7th Cir.1989); United States v. Andrews, 850 F.2d 1557, 1561-62 (11th Cir.1988); United States v. Valles-Valencia, 823 F.2d 381, 381-82 (9th Cir.1987); Gov’t of the Virgin Islands v. Hoheb, 777 F.2d 138, 142 n. 6 (3d Cir.1985), the Supreme Court has never expressly or even impliedly overruled the rule of consistency previously recognized by the Court in Morrison and Hart-zel. As the Tenth Circuit has noted, the argument that the rule of consistency is no longer viable after Powell “is substantially undercut by the fact that the Powell opinion does not discuss Hartzel or expressly overturn the traditionally recognized exception.” United States v. Suntar Roofing, Inc., 897 F.2d 469, 475 (10th Cir.1990).
Moreover, Powell did not concern or address inconsistent jury verdicts between two codefendants charged with conspiracy or participation in another similar criminal contract. The defendant in Powell was convicted of using the telephone to commit the crime of “conspiracy to possess with the intent to distribute and possession with intent to distribute cocaine,” but she was acquitted of knowingly and intentionally possessing cocaine with intent to distribute. Powell, 469 U.S. at 59-60, 105 S.Ct. 471. She argued that the verdicts were inconsistent because proof that she had conspired to possess cocaine with intent to distribute, or had so possessed cocaine, was an element of the telephone facilitation count. Id. at 60, 105 S.Ct. 471. The Court reaffirmed the holding of Dunn v. United States, 284 U.S. 390, 52 S.Ct. 189, 76 L.Ed. 356 (1932), that “[consistency in the verdict is not necessary.” Powell, 469 U.S. at 62-63, 105 S.Ct. 471. In so holding, Powell simply precludes a reversal based on inconsistency between verdicts on separate charges against a single defendant. Powell did nothing, however, to eliminate the rule requiring reversal of irreconcilable verdicts where one defen*591dant is acquitted and the other convicted of a crime that necessarily requires two people to participate in a criminal contract. See Andrews, 850 F.2d at 1570 (Clark, J., dissenting) (“I cannot agree that Powell should be expanded to let inconsistent conspiracy verdicts stand where one defendant is acquitted and the other convicted.”). Because nothing in Poivell purports to overrule Morrison and Hartzel, we will continue to follow the Supreme Court’s directly applicable precedent and “leave to the Court the prerogative of overruling its own decisions.” Agostini v. Felton, 521 U.S. 203, 237, 117 S.Ct. 1997, 138 L.Ed.2d 391 (1997).
In coming to the foregoing conclusion, we are mindful that the dicta of United States v. Newton and United States v. Crayton states that the rule of consistency “has no continuing validity.” United States v. Newton, 389 F.3d 631, 636 (6th Cir.2004), vacated in part on other grounds, — U.S. -, 126 S.Ct. 280, 163 L.Ed.2d 35 (2005); Crayton, 357 F.3d at 564. However, both Crayton and Newton more narrowly hold that “an individual’s conviction for conspiracy may stand, despite acquittal of other alleged coconspira-tors, when the indictment refers to unknown or unnamed conspirators and there is sufficient evidence to show the existence of a conspiracy between the convicted defendant and these other conspirators.” Crayton, 357 F.3d at 567 (quoting United States v. Anderson, 76 F.3d 685, 688-89 (6th Cir.1996)); see Newton, 389 F.3d at 636-37 (citing Anderson, 76 F.3d at 688-89). This narrow holding was the only discussion necessary to resolve the case. As the preeminent legal scholar Karl Llewellyn said, there is a “distinction between the ratio decidendi, the Court’s own version of the rule of the case, and the true rule of the case, what it will be made to stand for by another later court
For one of the vital elements of our doctrine of precedent is this: that any later court can always reexamine a prior case, and under the principle that the court could decide only what was before it, and that the older case must now be read with that in view, can arrive at the conclusion that the dispute before the earlier court was much narrower than that court thought it was, called therefore for the application of a much narrower rule. Indeed, the argument goes further. It goes on to state that no broader rule could have been laid down ex-cathedra, because to do that would transcend the powers of the earlier court.
Karl Llewellyn, The Bramble Bush 52 (1930). Or, as this Court recently said: “This Court considers as dicta any observation in the opinion of the court unnecessary to the holding in that case.” Peabody Coal Co. v. Director, Office of Workers’ Comp. Programs, 48 Fed.Appx. 140, 144 (6th Cir.2002). Because Crayton and Neivton were ultimately decided based on the rule of United States v. Anderson, the discussion of whether the rule of consistency is viable after Powell was unnecessary to the holding and therefore not binding on this Court.
Since we conclude that the Supreme Court has not overruled Morrison and Hartzel, the rule of consistency is applicable where, as in the instant case, a jury convicts only one of multiple defendants charged with committing the crime of murder for hire. Murder for hire requires at least two participants: the hiring party and the person hired. See Ramsey v. Commonwealth, 2 Va.App. 265, 343 S.E.2d 465, 470 (Va.Ct.App.1986) (noting that murder for hire “necessarily involve[s] at least two people”). An “essential element” of the crime of murder for hire is an agreement between the hiring party and *592the person hired that the latter will be compensated for his services. State v. Carpenter, 275 Conn. 785, 882 A.2d 604, 653 (Conn.2005); see Orsini v. State, 281 Ark. 348, 665 S.W.2d 245, 253 (Ark.1984) (To establish murder for hire, the government must prove that there was “an agreement to kill in exchange for something of value.”); State v. McGann, 199 Conn. 163, 506 A.2d 109, 116 (Conn.1986) (To establish a “hiring” relationship, the government must prove “the essential element of an agreement to compensate the [person hired] for his services.”); Commonwealth v. Gibbs, 533 Pa. 539, 626 A.2d 133, 138 (Pa.1993) (To establish murder for hire, the government must prove that the hiring party and the person hired “contracted to kill the victim.”). Therefore, the acquittal of all but one defendant “negates the possibility of an agreement” to kill between the sole remaining defendant and one of those acquitted of the murder for hire and “thereby denies, by definition, the existence of’ a “hiring” relationship. See Espinosa-Cerpa, 630 F.2d at 331. If the jury convicts only one of multiple defendants charged with the crime of murder for hire, this is a fatally inconsistent verdict requiring reversal.
Accordingly, the rule of consistency recognized in Morrison and Hartzel requires reversal of Getsy’s murder for hire conviction and the resulting death sentence because the other necessary participant, the hiring party, was acquitted of the same murder for hire specification. The acquittal of Santine of murder for hire based on substantially the same evidence signifies that the jury found no contract to kill the Serafinos, and Getsy cannot have acted alone since murder for hire requires a plurality of actors. Getsy’s murder for hire conviction is therefore irreconcilable with the jury verdict acquitting Santine of the same charge. As the Supreme Court established in Morrison and Hartzel, such an inconsistent verdict cannot stand. Moreover, the opinions in Furman rested upon a perception of just such inconsistency, see Furman, 408 U.S. at 309-10, 92 S.Ct. 2726 (Stewart, J., concurring); id. at 313, 92 S.Ct. 2726 (White, J., concurring), and the arbitrariness principle firmly established in Furman is offended by the irreconcilable jury verdicts in this case. Under these circumstances, the Ohio Supreme Court’s decision affirming Getsy’s death sentence without identifying or applying the governing Eighth Amendment principles was “contrary to” the principles clearly established in Furman, Morrison, and Hartzel.5
*593IV. Judicial Bias
Getsy claims that he did not receive a fair trial due to bias on the part of Judge McKay, the state court judge who presided over his trial. The bias charge stems from Judge McKay’s attendance, during Getsy’s trial, at an annual picnic hosted by Trumbull County judges at the home of Judge Ronald Rice’s mother. The picnic was also attended by Cynthia Rice, the wife of Judge Rice and the assistant prosecuting attorney who was trying Getsy’s case. Following the picnic, Judge McKay was involved in a single-car accident and was charged with driving under the influence of alcohol. The next day Judge McKay arrived for trial with bruises on his face and wearing sunglasses, and the trial continued without any mention of the incident. Although Judge McKay did not divulge the cause of his injuries to the parties, Getsy’s counsel learned of the picnic, the accident, and the judge’s arrest from local media coverage. Judge McKay was thereafter prosecuted by David P. Joyce, Prosecuting Attorney for Geauga County, acting as Special Prosecuting Attorney, and on September 5, 1996, Judge McKay pled guilty to driving under the influence of alcohol.
On August 26,1996, Getsy filed a Motion for Mistrial and a Motion for Recusal in the trial court. He also filed an Affidavit of Disqualification against Judge McKay in the Supreme Court of Ohio pursuant to Ohio Rev.Code Ann. § 2701.03. The motions alleged that the judge was socializing with the assistant prosecutor, thereby giving the appearance of impropriety. Getsy also asserted that the jury might have perceived that Judge McKay was favorably disposed toward the prosecution both because the judge was socializing with the assistant prosecutor and because the judge was facing prosecution for driving under the influence. (J.A. at 516-23.)
On August 27, 1996, the Chief Justice of the Supreme Court of Ohio denied the Affidavit of Disqualification, stating:
The mere fact that a judge and an attorney attend the same social event does not mandate the judge’s disqualification from pending cases involving that attorney. ... Moreover, I cannot conclude that Judge McKay had any duty to disclose his attendance at the event in question, either before or after the event, or that his nondisclosure was the product of any animosity or bias toward the defendant in this case. The record is devoid of any evidence that demonstrates the existence of any bias, prejudice, or disqualifying interest based on the claims of the affiants.
In re Disqualification of McKay, 77 Ohio St.3d 1249, 674 N.E.2d 359, 359 (Ohio 1996). The Chief Justice primarily relied on Judge McKay’s affidavit, which indicated that any contact the judge had with the assistant prosecuting attorney at the picnic consisted of the “passing of simple social amenities.” Id.
After the Chief Justice denied the application, Judge McKay brought in a fellow Trumbull County judge to voir dire the jurors regarding the media coverage of Judge McKay’s arrest. Only two jurors had seen the newspaper articles about Judge McKay’s accident and arrest, and both indicated that it would not affect their ability to be fair and impartial. Concluding that the jury had not been “impaired,” Judge McKay then denied the Motion for *594Mistrial and the Motion for Recusal without a hearing.
The Due Process Clause of the Fourteenth Amendment requires that a defendant be afforded a “fair trial in a fair tribunal before a judge with no actual bias against the defendant or interest in the outcome of his particular case.” Bracy v. Gramley, 520 U.S. 899, 904-05, 117 S.Ct. 1793, 138 L.Ed.2d 97 (1997) (citations omitted); see In re Murchison, 349 U.S. 133, 136, 75 S.Ct. 623, 99 L.Ed. 942 (1955) (“A fair trial in a fair tribunal is a basic requirement of due process. Fairness of course requires an absence of actual bias in the trial of eases.”). This Court has explained that “[i]f a habeas court determines that bias by a state judge resulted in a constitutional violation, then the court is required to overturn the state court decision.” Alley v. Bell, 307 F.3d 380, 386 (6th Cir.2002). Further, this Court looks to “the Supreme Court’s decision in [Liteky v. United States ] to provide the standard for deciding judicial bias claims; in that case, the Court explained that ‘the pejorative connotation of the terms ‘bias’ and ‘prejudice’ demands that they be applied only to judicial predispositions that go beyond what is normal and acceptable.’ ” Id. (quoting Liteky v. United States, 510 U.S. 540, 552, 114 S.Ct. 1147, 127 L.Ed.2d 474 (1994)). To state a due process claim of judicial bias, a “defendant must show either that actual bias existed, or that an appearance of bias created a conclusive presumption of actual bias.” United States v. Lowe, 106 F.3d 1498, 1504 (10th Cir.1997); see also Anderson v. Sheppard, 856 F.2d 741, 746 (6th Cir.1988) (“[W]e require not only an absence of actual bias, but an absence of even the appearance of judicial bias.”).
In order for us to evaluate whether Get-sy was deprived of his right to a fair trial, we must know more about the extent of Judge McKay’s contact with the assistant prosecutor and the effect of the judge’s arrest and prosecution on his ability to be neutral. The record before us is inadequate for a meaningful review of Getsy’s claim of judicial bias, and we, therefore, grant Getsy’s request for an evidentiary hearing. AEDPA permits a district court to hold an evidentiary hearing in a habeas case only in limited circumstances. It provides:
If the applicant has failed to develop the factual basis of a claim in State court proceedings, the court shall not hold an evidentiary hearing on the claim unless the applicant shows that—
(A) the claim relies on—
(i) a new rule of constitutional law, made retroactive to cases on collateral review by the Supreme Court, that was previously unavailable; or
(ii) a factual predicate that could not have been previously discovered through the exercise of due diligence; and
(B) the facts underlying the claim would be sufficient to establish by clear and convincing evidence that but for constitutional error, no reasonable factfinder would have found the applicant guilty of the underlying offense.
28 U.S.C. § 2254(e)(2).
Although the requirements of § 2254(e)(2) are onerous, “only a prisoner who has neglected his rights in state court need satisfy these conditions.” (Michael) Williams v. Taylor, 529 U.S. 420, 435, 120 S.Ct. 1479, 146 L.Ed.2d 435 (2000).6 By the terms of its opening clause, § 2254(e)(2) applies only to prisoners who *595have “failed to develop the factual basis of a claim in State court proceedings.” Id. at 430, 120 S.Ct. 1479. If the prisoner has failed to develop the facts, “himself or herself contributing to the absence of a full and fair adjudication in state court, § 2254(e)(2) prohibits an evidentiary hearing to develop the relevant claims in federal court, unless the statute’s other stringent requirements are met.” Id. at 437, 120 S.Ct. 1479.
In determining whether the prisoner must satisfy the requirements of § 2254(e)(2), the question is not whether the petitioner has succeeded in developing the record, but whether the petitioner has diligently attempted to do so. In (Michael) Williams v. Taylor, the Supreme Court held that “a failure to develop the factual basis of a claim is not established unless there is lack of diligence, or some greater fault, attributable to the prisoner or the prisoner’s counsel.” Id. at 432, 120 S.Ct. 1479. For purposes of § 2254(e)(2), diligence requires the prisoner to make “a reasonable attempt, in light of the informa^ tion available at the time, to investigate and pursue claims in state court; it does not depend ... upon whether those efforts could have been successful.” Id. at 435, 120 S.Ct. 1479. As the Supreme Court explained, “[diligence will require in the usual case that the prisoner, at a minimum, seek an evidentiary hearing in state court in the manner prescribed by state law.” Id. at 437, 120 S.Ct. 1479.
We conclude that Getsy made a reasonable attempt, in light of the information available at the time, to develop the factual basis of his judicial bias claim. In his Motion for Mistrial, Getsy requested that he be allowed to question “certain individuals,” including Cynthia Rice and Judge McKay, about the contact between the judge and the assistant prosecutor. (J.A. at 518.) Getsy was not afforded the opportunity to examine the relevant witnesses. In his petition for post-conviction relief, Getsy sought discovery in support of his judicial bias claim, specifically requesting further information about the contact between the judge and the assistant prosecutor and about the effect of the incident on the jury. (J.A. at 1358.) The state court dismissed Getsy’s petition without a hearing. (J.A. at 1424.) Getsy also repeatedly requested, and was denied, an evidentiary hearing in state court on the issue. Getsy’s failure to develop the factual basis of his judicial bias claim was not due to a lack of diligence, and he therefore need not satisfy the requirements of § 2254(e)(2) with respect to this claim. Because Getsy never received an eviden-tiary hearing and consequently the record before us fails to clarify facts central to the determination of Getsy’s claim of judicial bias, we remand for an evidentiary hearing on this claim.
V. Other Issues
Because we are vacating Getsy’s death sentence on Eighth Amendment grounds, we do not reach the alternative grounds raised by Getsy in the challenge to his death sentence, including ineffective assistance of counsel at the penalty phase, insufficient evidence to support the statutory aggravating circumstance of murder for hire,7 and the cumulative effect of the errors.
*596Getsy also raises 3 other issues that he claims warrant a granting of the writ and a new trial: (1) Getsy’s confession should not have been introduced at trial as it was not voluntarily given; (2) Getsy was denied the right to a fair and impartial jury drawn from a representative cross-section of the community; and (3) the State improperly singled Getsy out for prosecution and imposition of the death penalty.
A. Introduction of Confession at Trial
Getsy was convicted in large part based on his videotaped confession to the police that he committed the murder of Ann Ser-afino and the attempted murder of Chuck-ie Serafino, which he made after he was arrested on July 7, 1995. Getsy argues that the waiver of his Miranda rights and his subsequent confession were not made voluntarily because he was in custody and deprived of food, rest, and the advice of counsel and family for an extended period of time. We do not have before us any question concerning whether Getsy’s confession was unknowing and unintelligent. See Colorado v. Spring, 479 U.S. 564, 573, 107 S.Ct. 851, 93 L.Ed.2d 954 (1987) (explaining that claims regarding Miranda waivers must demonstrate not only that the confession was voluntary but also that the confession was knowing and intelligent).
The state court correctly noted that police overreaching is necessary for a confession to be found involuntary under the Due Process Clause of the Fourteenth Amendment. See Colorado v. Connelly, 479 U.S. 157, 164, 107 S.Ct. 515, 93 L.Ed.2d 473 (1986); Clark v. Mitchell, 425 F.3d 270, 283 (6th Cir.2005). In Colorado v. Connelly, the defendant had approached a police officer and insisted on confessing to a murder committed a year earlier. The defendant was later diagnosed as suffering from schizophrenia, which interfered with his ability to make free and rational choices. The Supreme Court held that the defendant’s deficient mental condition was not a sufficient basis from which to find that the defendant’s confession was involuntary. Rather, the Court held that “coercive police activity is a necessary predicate to the finding that a confession is not ‘voluntary’ within the meaning of the Due Process Clause of the Fourteenth Amendment.” Connelly, 479 U.S. at 167, 107 S.Ct. 515.
Getsy has not demonstrated that there was police overreaching in his case. Getsy was arrested at around 10:00 p.m. on July 7, 1995, transported to the Hubbard Township Police Station, and apprised of his Miranda rights. Fewer than three hours later, Getsy waived his Miranda rights and confessed to the murder. The interview itself was of relatively short duration, lasting less than one hour. During the interview, Getsy was not subjected to any threats or physical deprivation. Getsy did not asked the police for food or an opportunity to rest, and they did not deny either to him. Although the transcript of Getsy’s statement reveals that he was frightened, he was frightened of Santine, not of the police officers questioning him. Although *597the transcript shows that the police assured Getsy that Santine would not harm him, Getsy did not offer any evidence to show that these assurances impacted his decision to give his post-arrest confession. Thus, there is no merit to Getsy’s argument that his confession was involuntary or unconstitutionally admitted.
B. Fair and Impartial Jury
In this claim, Getsy argues that his jury was not fair and impartial because: (1) pretrial publicity infected the jury pool; (2) the trial court improperly limited voir dire; (3) the trial court failed to remove for cause jurors who stated that they would automatically impose a death sentence upon a conviction; and (4) prospective jurors were asked to commit themselves to imposing the death penalty. Contrary to Getsy’s contention, nothing in the record establishes that Getsy was denied the right to a fair and impartial jury. A review of the transcripts of the voir dire reveals that the court questioned prospective jurors about their exposure to pretrial publicity and excused all jurors who indicated that they could not be impartial; the trial court did not unreasonably or arbitrarily restrict the questioning of potential jurors during voir dire; the three jurors who Getsy asserts would automatically vote to impose the death penalty indicated that they could consider all available options; and neither the trial court nor the prosecutor sought commitments from prospective jurors to impose the death penalty-
Getsy also contends that his jury was not fair and impartial because the trial court improperly excused for cause three jurors who expressed opposition to the death penalty. The state court properly applied the standard established in Wainwright v. Witt, 469 U.S. 412, 105 S.Ct. 844, 83 L.Ed.2d 841 (1985), for determining when a prospective juror may be excluded for cause because of his or her views on capital punishment. That standard is whether the juror’s views would “prevent or substantially impair the performance of his duties as a juror in accordance with his instructions and his oath.” Id. at 424, 105 S.Ct. 844. The Ohio Supreme Court specifically adopted the Witt standard in State v. Rogers, 17 Ohio St.3d 174, 478 N.E.2d 984, 989 (Ohio 1985), vacated on other grounds by 474 U.S. 1002, 106 S.Ct. 518, 88 L.Ed.2d 452 (1985), and Ohio Rev.Code Ann. § 2945.25(C)8 does not impose a higher standard than that set forth in Witt, see State v. Roe, 41 Ohio St.3d 18, 535 N.E.2d 1351, 1357 (Ohio 1989); State v. Frazier, 73 Ohio St.3d 323, 652 N.E.2d 1000, 1007 (Ohio 1995). The record reveals that Juror Nos. 107, 140, and 185 were properly excluded under the standard set forth in Witt because, although these jurors equivocated in their answers, all three indicated that they could not follow the law and impose the death sentence, even if appropriate. (J.A. at 3008, 3133, 3332.)
C. Selective Prosecution
Getsy contends that the State improperly engaged in selective prosecution *598by seeking the death penalty for him and not for his three codefendants. To support his claim of selective prosecution, Get-sy bears the “heavy burden” of establishing “that, while others similarly situated have not generally been proceeded against because of conduct of the type forming the basis of the charge against him, he has been singled out for prosecution.” United States v. Berrios, 501 F.2d 1207, 1211 (2d Cir.1974). He must also demonstrate “that the government’s discriminatory selection of him for prosecution has been invidious or in bad faith, i.e., based upon such impermissible considerations as race, religion, or the desire to prevent his exercise of constitutional rights.” Id.
We agree with the Ohio Supreme Court and the district court that this claim is unsupported by the record. It appears from the record that the codefendants in this case were similarly charged with the aggravated murder of Ann Serafino, with three death penalty specifications: (1) the aggravated murder was committed in conjunction with the purposeful killing of or attempt to kill two or more persons; (2) murder for hire; and (3) felony murder. The fact that two of the codefendants were offered a plea agreement in which the death penalty specifications were dismissed, and that a jury acquitted one codefendant of the death penalty specifications does not indicate that Getsy was selectively prosecuted. Further, nothing in the record suggests that the offer of a plea bargain to Hudach and McNulty or the lack of an offer to Getsy was based upon improper motives. The record is thus clear that Getsy cannot establish that he was singled out for prosecution.
VI. Conclusion
We hold that Getsy’s death sentence violates Furman, Enmund, and Morrison in that its imposition is arbitrary and disproportionate and results in inconsistent verdicts. We, therefore, reverse and vacate the judgment insofar as it leaves undisturbed the death sentence imposed. The State is granted 180 days after the judgment in this case becomes final in the federal judicial system to reconsider in light of this opinion Getsy’s sentence under Ohio law. We also remand the case for an evidentiary hearing regarding the claim of judicial bias and for further proceedings not inconsistent with this opinion.
. Aristotle's view that "like cases should be treated alike” has long been a foundational principal in the U.S. legal system. See, e.g., Jennifer B. Wriggins, Torts, Race, and the Value of Injury, 1900-1949, 49 How. L.J. 99, 101 n.10 (2005); Morris B. Hoffman, The *586Case for Jury Sentencing, 52 Duke LJ. 951, 1000 n.179 (2003); Catherine Weiss & Louise Melling, The Legal Education of Twenty Women, 40 Stan. L.Rev. 1299, 1347 n.120 (1988); Peter Westen, The Empty Idea of Equality, 95 Harv. L.Rev. 537, 543 n.20 (1982); cf. H.L.A. Hart, The Concept of Law 155 (1961) (deeming the phrase "[t]reat like cases alike" a "leading precept” of justice).
. The dissent also argues incorrectly that our consideration of the "comparative proportionality" of the sentences in this case is foreclosed by our precedents relying on Pulley v. Harris. See, e.g., Williams v. Bagley, 380 F.3d 932, 962-63 (6th Cir.2004); Wickline v. Mitchell, 319 F.3d 813, 824 (6th Cir.2003); Smith v. Mitchell, 348 F.3d 177, 214 (6th Cir.2003); Bowling v. Parker, 344 F.3d 487, 521 (6th Cir.2003); Buell v. Mitchell, 274 F.3d 337, 369 (6th Cir.2001). In each of these cases, we rejected claims regarding inadequate appellate review of the proportionality of death sentences, reasoning that the Constitution does not require the State to provide for a system of proportionality review. Our precedents interpret Pulley as holding that a system of comparative proportionality review is not constitutionally required, and the state therefore has "great latitude” in defining its system of proportionality review. See Buell, 274 F.3d at 369. Getsy's proportionality argument does not implicate our precedents relying on Pulley because Getsy does not challenge Ohio’s system of proportionality review. Rather, Getsy challenges the imposition of disproportionate sentences for the very same crime stemming from the very same facts.
. The origins of the rule of consistency can be traced back more than four centuries to the case of Marsh v. Vauhan, 78 Eng. Rep. 937 (Q.B.1599), in which two defendants were indicted and tried jointly for conspiracy, with the result that one was convicted and the other acquitted. The court quashed the lone defendant’s conviction, reasoning in a one paragraph opinion that "one cannot conspire alone.” Id. at 937. Subsequent decisions addressing irreconcilable or repugnant jury verdicts in conspiracy and other cases based on a criminal agreement between two parties adhered to the Marsh rule in quashing inconsistent verdicts. See, e.g., R. v. Grimes, 87 Eng. Rep. 142 (K.B.1688); R. v. Kinnersley, 93 Eng. Rep. 467 (K.B.1719); R. v. Thompson, 117 Eng. Rep. 1100 (Q.B.1851).
. Some courts in non-death penalty cases have refused to apply the rule of consistency to inconsistent verdicts resulting from separate trials. See United States v. Newton, 389 F.3d 631, 636 (6th Cir.), vacated in part on other grounds, - U.S. -, 126 S.Ct. 280, 163 L.Ed.2d 35 (2005); United States v. Crayton, 357 F.3d 560, 564 (6th Cir.2004); Cortis v. Kenney, 995 F.2d 838, 840 (8th Cir.1993); United States v. Sachs, 801 F.2d 839, 845 (6th Cir.1986); United States v. Lewis, 716 F.2d 16, 22 (D.C.Cir.1983); United States v. Sangmeister, 685 F.2d 1124, 1126-27 (9th Cir.1982); United States v. Espinosa-Cerpa, 630 F.2d 328, 333 (5th Cir.1980). These courts reason that "it is not necessarily inconsistent for two juries to reach differing results” because "different juries may hear different evidence.” Sachs, 801 F.2d at 845. These courts also reason that application of the rule of consistency in this context "would be blatantly inconsistent with the Supreme Court’s decision in Standefer.” See Espinosa-Cerpa, 630 F.2d at 333.
In Standefer v. United States, 447 U.S. 10, 100 S.Ct. 1999, 64 L.Ed.2d 689 (1980), the Supreme Court held that a defendant, who would have been an accessory at common law, may be convicted even though the named principal has been acquitted in a separate trial. The holding in Standefer rested on Congress’s express intent to make those who were accessories at common law principal offenders, thereby permitting their indictment and conviction for the substantive offense. Id. at 19, 100 S.Ct. 1999. Contrary to the reasoning of the courts refusing to apply the rule of consistency to inconsistent verdicts resulting from separate trials, neither Standefer nor any subsequent Supreme Court decision has proscribed application of the rule in this context.
The cases from the courts of appeals proscribing application of the rule of consistency to inconsistent verdicts resulting from separate trials were not capital cases. In refusing to apply the rule in this context, these cases protect the functions of the jury at the risk of disparate or arbitrary results. Such risk cannot be tolerated in a case in which the defendant’s life is at stake. As the Supreme Court has often stated:
[T]he penalty of death is qualitatively different from a sentence of imprisonment, however long. Death, in its finality, differs more from life imprisonment than a 100-year prison term differs from one of only a year or two. Because of that qualitative difference, there is a corresponding difference in the need for reliability in the determination that death is the appropriate punishment in a specific case.
Woodson v. North Carolina, 428 U.S. 280, 305, 96 S.Ct. 2978, 49 L.Ed.2d 944 (1976). It would be inconsistent with the heightened need for "reliability” in the capital sentencing decision to refuse to apply the rule of consistency.
Although this circuit has held that the rule of consistency does not apply to inconsistent verdicts resulting from separate trials in conspiracy cases, see Newton, 389 F.3d at 636; Crayton, 357 F.3d at 564; Sachs, 801 F.2d at 845, we have not extended this holding either to capital cases or to cases involving substantive crimes, such as adultery, incest, bigamy, dueling, or murder for hire, that necessarily *589involve at least two participants. The instant indictment charged Getsy with conspiracy to murder, but he was not convicted of this count. He was convicted of murder for hire. This was a substantive offense. Conspiracy is separate from the substantive offense that is the object of the agreement. United States v. Felix, 503 U.S. 378, 389-90, 112 S.Ct. 1377, 118 L.Ed.2d 25 (1992). The rule allowing inconsistent verdicts in conspiracy cases has not been applied and should not be applied to inconsistent verdicts on the substantive offense of murder for hire in the same case. The law has excused inconsistent verdicts in run-of-the-mill conspiracy cases, but it has not excused inconsistent verdicts on a substantive offense requiring the participation of two people. We should not start now to permit such arbitrary, inconsistent verdicts— especially in a capital case.
. Contrary to the dissent’s characterization of our holding, we merely hold that the rule firmly established in Morrison and Hartzel provides compelling evidence of the arbitrariness of Getsy's death sentence. Our dissenting colleague concludes that these cases do not alter the conclusion that the rule of consistency did not survive Powell. In so concluding, our dissenting colleague fails to understand that Morrison and Hartzel are distinguishable from the line of cases regarding inconsistency between verdicts on separate charges against one defendant. It is true, as the dissent points out, that Powell and a number of earlier Supreme Court cases have held generally that inconsistency between verdicts returned as to a single defendant is insufficient reason to upset a conviction. However, none of these cases involved multiple defendants charged with jointly committing an offense, like conspiracy or murder for hire, that requires the participation of at least two parties in a criminal agreement. Because Powell did not even involve a criminal agreement between two parties, one of whom is acquitted of participation in the agreement, its holding does not affect the rule recognized in Morrison and Hartzel. See Harris v. Rivera, 454 U.S. 339, 345 n. 13, 102 S.Ct. 460, 70 L.Ed.2d 530 (1981) (acknowledging the decision in Hartzel as distinguishable from the Supreme Court’s cases with respect to inconsistency between verdicts on separate charges against one defendant). Thus, Powell does not men*593tion or purport to change the doctrine of Morrison and Hartzel and the age-old common law rule to the same effect. We are at a loss to understand why our dissenting colleague strains so hard to get around applying the traditional doctrine — especially in a capital case where life is at stake. Not only are we constitutionally bound to apply the Morrison/Hartzel doctrine, we are also statutorily bound under AEDPA.
. This case is not to be confused with the case (Terry) Williams v. Taylor, 529 U.S. 362, 120 S.Ct. 1495, 146 L.Ed.2d 389 (2000), which also concerns the interpretation of certain provisions of § 2254, and which was decided on the same day (April 18, 2000).
. When reviewing a defendant’s conviction, our concerns about double jeopardy inform the general rule that we must consider a sufficiency of the evidence challenge to a conviction first when that issue is raised. See United States v. Aarons, 718 F.2d 188, 189 n. 1 (6th Cir.1983) (“Where the sufficiency of the evidence is properly before us, we consider that issue first because it is determinative of whether the appellant may be retried."); *596Delk v. Atkinson, 665 F.2d 90, 93 n. 1 (6th Cir.1981) ("Several courts including this one have indicated that where it is claimed on appeal from a federal conviction that the evidence was insufficient, the reviewing court is required to decide the sufficiency question even though there might be other grounds for reversal which would not preclude retrial.”); United States v. Orrico, 599 F.2d 113, 116 (6th Cir.1979) ("We decide the issue of sufficiency of the evidence, rather than admissibility, because the former issue is determinative of the question whether [the defendant] may be retried.”). In these circumstances, however, we need not reach Getsy's sufficiency of the evidence claim because our rule of consistency holding means that Getsy cannot face retrial on the murder for hire specification.
. Section 2945.25 provides, in relevant part: A person called as a juror in a criminal case may be challenged for the following causes:
$ $ $ $ $ $
(C) In the trial of a capital offense, that he unequivocally states that under no circumstances will he follow the instructions of a trial judge and consider fairly the imposition of a sentence of death in a particular case. A prospective juror’s conscientious or religious opposition to the death penally in and of itself is not grounds for a challenge for cause. All parties shall be given wide latitude in voir dire questioning in this regard.