GILMAN, J., delivered the opinion of the court, in which ROGERS, J., joined. MARTIN, J. (pp. 250-58), delivered a separate dissenting opinion.
OPINION
RONALD LEE GILMAN, Circuit Judge.
Michael W. Benge was convicted of aggravated murder and aggravated robbery in violation of Ohio law and was sentenced to death. He filed a petition for habeas corpus that raised sixteen alleged errors in the state-court proceedings. The district court denied the petition, but granted a Certifícate of Appealability (COA) as to seven of Benge’s claims. For the reasons set forth below, we AFFIRM the judgment of the district court.
I. BACKGROUND
A. Factual background
The Ohio Supreme Court set forth the following facts and procedural history of this case in State v. Benge, 75 Ohio St.3d 136, 661 N.E.2d 1019, 1022-24 (Ohio 1996):
In the early morning hours of February 1, 1993, a car belonging to Judith Gabbard, defendant-appellant Michael W. Benge’s live-in girlfriend, was found abandoned on the west side of the Miami River in Hamilton, Ohio. The vehicle was found near the river with the front passenger-side tire stuck in a gully. After the vehicle was towed to the impound lot, the tow-truck operator observed blood on the front bumper and passenger side of the car and notified the police.
The police returned to the area where the car was found and discovered the body of Judith Gabbard in the Miami River. Her body had been weighed down with a thirty-five pound piece of concrete which had been placed upon her head and chest. One of the pockets on the jacket Gabbard was wearing was empty and turned inside out. She still had in her possession her checkbook, cash and jewelry. The police retrieved [239]*239a tire iron, or lug wrench, from the river approximately twelve to fifteen feet from where Gabbard’s body was found. A jack and spare tire were found in Gabbard’s trunk, but no lug wrench was discovered.. Police removed lug nuts from the vehicle, which were sent to a laboratory and compared with the lug wrench. Although no positive match was made, the lug nuts did bear markings which were similar to the lug wrench.
The police gathered other physical evidence from the scene which was also tested by a forensic laboratory. Strands of hair and type A blood (which both Gabbard and appellant had) were found on the driver’s side front tire. Smears of blood were also discovered above the passenger-side headlight and on the fender. Police also found a pool of blood with a tire track through it and blood contained in the tire treads. According to one of the investigative detectives, this evidence indicated that the car had been driven through the blood and through the hair of the victim.
An autopsy was performed, which revealed that the victim had suffered a number of blows to the head with a long blunt object which produced pattern abrasions and multiple skull fractures, one of which was circular in nature. According to the coroner, the victim died of brain injuries secondary to multiple skull fractures which were inflicted with a blunt object.
The police apprehended Benge the next day, on February 2, 1993. When the detectives approached Benge, on the street, they observed him drop Judith Gabbard’s ATM card to the ground. They picked up the card, arrested Benge, and took him into the station for questioning. After being read his Miranda warnings, Benge agreed to talk to the detectives. Benge told police that two black men in a Bronco had chased him and Gabbard to the river and that their car had gotten stuck. Benge claimed that one of the men injured Gabbard and took her ATM card while the other held him at gunpoint, demanding the ATM code word. When Benge refused to tell him, the man returned the ATM card to him. Benge escaped by jumping into the river. As he swam away, he heard Gabbard screaming as the men beat her. The detectives told Benge they did not believe his story. Benge told them he thought he should talk to a lawyer. The questioning ceased at that point.
A short time later, Benge told police he was willing to talk. Benge signed a Miranda warning card indicating that he waived his Miranda rights. Benge then gave the police a tape-recorded statement in which he recounted a different version of what happened the night before. Benge told police that he had driven to the riverbank with Gabbard so that they could talk. He said that they had argued over the fact that he was addicted to crack cocaine. Gabbard also accused him of being unfaithful to her. Benge then said he got out of the vehicle to urinate. At that point, he said Gab-bard tried to run him down, but the car got stuck in the mud. Benge said that he became enraged, pulled Gabbard out of the car, and began beating her with a metal pipe he found lying on the ground. Benge said he threw her body into the river, face down, disposed of the weapon and swam across the river. He did not recall whether he put any rocks or cement on her body. Benge then went to the home of his friend, John Fuller, to get dry clothes, which Fuller’s fiancee, Awantha Shields, provided.
During this second interrogation, Benge was questioned about the ATM [240]*240card, why he had dropped it when he saw the police, and whether he had used it after killing Gabbard. Benge said he threw down the card because he was scared and he knew he would not need it anymore. He also told police that he had not used the card since he killed Gabbard, although he did allow a man by the name of Baron Carr to use the card once to get money to purchase crack cocaine. Benge claimed that the only reason he had the card in his possession was because he and Gabbard had used it on January 31, 1993 before they went out that evening. However, the police discovered through retrieving ATM records that no transaction had taken place on January 31,1993 and that two transactions were made following Gabbard’s death; on February 1, 1993 at 2:45 a.m., a $200 withdrawal was made, and on February 2, 1993 at 12:01 a.m., another $200 was withdrawn.
Benge was indicted on one count of aggravated murder in violation of R.C. 2903.01(B) with death penalty specifications under R.C. 2929.04(A)(3) (offense committed for the purpose of escaping detection for another offense) and R.C. 2929.04(A)(7) (offense committed during the commission of an aggravated robbery) as well as for aggravated robbery and gross abuse of a corpse. Benge pleaded no contest to gross abuse of a corpse. The case proceeded to trial on the other charges.
At trial, the state called Awantha Shields, who testified that in the early morning hours of February 1, 1993, Benge arrived at the house she shared with John Fuller, wearing wet clothes and asking for John. Benge also asked her if she had ever killed anyone. He then told her that he and his girlfriend had “got into it” earlier, that it blew over, and that they went to the river bank. He then told her that they had started fighting and that he hit her in the head no more than ten times with a crowbar, put rocks over her head and pushed her in the river. Benge told her that he had killed his girlfriend to get her “Jeanie” card. He also said that if the police questioned him he would lie and say that a couple of black guys jumped him and his girlfriend and beat his girlfriend up. He also told her that he had given her ATM card to a guy named Baron to get $200 to buy crack cocaine but that he never saw the money.
Larry Carter testified that he and Baron Carr ran into Benge in the early morning of February 1, 1993. Benge, whose clothes were wet, asked Carter to excuse how he smelled but that he had just swum in the river. Carter thought Benge was kidding. Benge told him he had given John $20 to buy crack cocaine for him and said that he could get more money. Carter drove Benge and Carr to a Society Bank where Benge withdrew $200 from an ATM; Carter then bought crack cocaine for Benge. Carter later drove Benge to Fuller’s house. Later that next night, Carter and Baron Carr withdrew another $200 from Gab-bard’s account using her ATM card so that they could buy drugs for Benge. However, to avoid giving the drugs or money to Benge, the two men conjured up a story and told Benge that his girlfriend had closed the account. Benge insisted that she had not.
Benge took the stand on his own behalf and reiterated what he had told police during his second interrogation, including that Gabbard had tried to run him down and that he was in a rage when he killed her. Benge also claimed that he had permission to use Gabbard’s ATM card and did not rob her. On cross-examination, he admitted losing [241]*241his job in January 1993 due to his crack cocaine habit and that he had no income at the time he killed Gabbard.
Benge was convicted of all counts and specifications. Thereafter, the jury recommended that he be sentenced to death, and that recommendation was accepted by the trial court. The court of appeals affirmed Benge’s convictions and death sentence.
The Ohio Supreme Court also affirmed Benge’s convictions and death sentence. Id. at 1029. After being denied any relief in state postconviction proceedings, Benge filed a petition for habeas corpus in the district court, raising sixteen claims for relief. Benge v. Johnson, 312 F.Supp.2d 978, 986 (S.D.Ohio 2004). The district court denied Benge’s petition, id. at 1037, but granted a Certificate of Appealability (COA) as to seven of the claims.
II. ANALYSIS
A. Standard of review
Under the Antiterrorism and Effective Death Penalty Act of 1996 (AED-PA), a federal court
may not grant a writ of habeas to a petitioner in state custody with respect to any claim adjudicated on the merits in state court unless (1) the state court’s decision “was contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court” ... or (2) the state court’s decision “was based on an unreasonable determination of the facts in light of the evidence presented in the State court proceedings.”
Taylor v. Withrow, 288 F.3d 846, 850 (6th Cir.2002) (quoting 28 U.S.C. § 2254(d)). This standard requires that federal courts give considerable deference to state-court decisions. Herbert v. Billy, 160 F.3d 1131, 1135 (6th Cir.1998) (“[AEDPA] tells federal courts: Hands off, unless the judgment in place is based on an error grave enough to be called unreasonable.”) (citation and quotation marks omitted).
The first line of analysis under AEDPA involves the consistency of the state-court decision with existing federal law. A state-court decision is considered “contrary to ... clearly established Federal law” if it is “diametrically different, opposite in character or nature, or mutually opposed.” Williams v. Taylor, 529 U.S. 362, 405, 120 S.Ct. 1495, 146 L.Ed.2d 389 (2000) (quotation marks omitted). Alternatively, to be found an “unreasonable application of ... clearly established Federal law,” the state-court decision must be “objectively unreasonable” and not simply erroneous or incorrect. Id. at 409-11, 120 S.Ct. 1495.
The second line of analysis under AEDPA concerns findings of fact made by the state courts. AEDPA requires federal courts to accord a high degree of deference to such factual determinations. “A federal court is to apply a presumption of correctness to state court findings of fact for habeas corpus purposes unless clear and convincing evidence is offered to rebut this presumption. The appeals court gives complete deference to the federal district court’s and state court’s findings of fact supported by the evidence.” McAdoo v. Elo, 365 F.3d 487, 493-94 (6th Cir.2004) (citations omitted).
B. Summary of Benge’s claims on appeal
The seven issues covered by the COA are as follows: (1) whether the prosecution withheld favorable evidence, (2) whether the defense counsel had an actual conflict of interest, (3) whether prosecutorial misconduct in the guilt and penalty phases violated Benge’s constitutional rights, (4) whether a jury instruction incorrectly pre-[242]*242eluded the jury from considering the affirmative defense of voluntary manslaughter, (5) whether there was sufficient evidence to support Benge’s convictions, (6) whether outbursts by the victim’s family both inside and outside of the courtroom violated Benge’s constitutional rights, and (7) whether Benge’s counsel was ineffective.
After carefully considering the record on appeal, the briefs of the parties, and the applicable law, and having had the benefit of oral argument, we find no error in the district court’s denial of Benge’s habeas corpus petition. Because the reasoning that supports the judgment for the warden has been clearly and persuasively articulated by the district court in two thorough and comprehensive opinions, the issuance of a detailed written opinion by us on all seven issues would be unduly duplicative. We therefore adopt the reasoning of the district court as to issues (3), (5), (6), and (7) without further comment, but offer additional analysis on issues (1), (2), and (4), which are the ones that occupied the majority of the time at oral argument.
C. Whether the prosecution impermis-sibly withheld evidence that was favorable to Benge
Benge contended in his state postconviction proceedings that the prosecution withheld potentially exculpatory information in violation of Brady v. Maryland, 373 U.S. 83, 83 S.Ct. 1194, 10 L.Ed.2d 215 (1963), and its progeny. The information that Benge contends was not properly disclosed consists of a statement that Fuller gave to the police and Fuller’s grand jury testimony. In the statement, Fuller said that he was home when Benge arrived on the night of the murder, and he described several incriminating statements made by Benge. Fuller also said that he may have missed parts of the conversation between Benge and Shields. In his grand jury testimony, Fuller said that he got home after Benge was already there, and that he spoke with Benge outside of Shields’s presence, at which time Benge made a number of incriminating statements. State v. Benge, No. CA 97-08-163, 1998 WL 204941, at *4-5 (Ohio Ct.App.1998). According to Benge, this information could have been used to impeach Shields’s testimony concerning the alleged admissions by Benge on the night of the murder. Id.
1. Ohio Court of Appeals ruling
The Ohio Court of Appeals is the last state court to review this issue that Benge raised in postconviction proceedings. It performed a detailed examination of Fuller’s statement to the police and grand jury testimony prior to Benge’s trial, and his deposition testimony and affidavit following Benge’s convictions. Id. at *4-6. According to the state court, Fuller’s statement and grand jury testimony were not favorable to Benge because they would not have impeached Shields, but instead would have bolstered her testimony. Id. at *6. The court then went on to address Fuller’s postconviction affidavit, which claims that Benge was never alone with Shields and that Benge never stated that he killed Gabbard for her ATM card. It concluded that the affidavit was not credible because it completely contradicted Fuller’s statement to the police and grand jury testimony, and that such recantations are deemed unreliable. Id.
2. District court ruling
After the district court initially found that Benge had withdrawn his Brady claim, Benge asked the court to reconsider its ruling. Out of “an abundance of caution,” the district court granted the motion to reconsider its original disposition of this claim and issued a separate opinion denying the claim on the merits. Benge v. [243]*243Johnson, No. C-1-98-861, slip op. at 1-12 (S.D.Ohio July 7, 2004). In that opinion, the district court concluded that the Ohio Court of Appeals had not unreasonably applied clearly established federal law or unreasonably determined the facts based on the evidence presented. Id. at 12. The district court also performed a detailed review of the evidence and agreed with the Ohio Court of Appeals that Fuller’s statement and grand jury testimony were not exculpatory evidence subject to Brady disclosure. Id.
3. Our review
Brady requires the government to “turn over evidence in its possession that is both favorable to the accused and material to guilt or punishment,” Pennsylvania v. Ritchie, 480 U.S. 39, 57, 107 S.Ct. 989, 94 L.Ed.2d 40 (1987), including evidence that could be used the impeach the credibility of a government witness. Gig-lio v. United States, 405 U.S. 150, 154-55, 92 S.Ct. 763, 31 L.Ed.2d 104 (1972). In order for evidence to be considered “material,” the court must conclude that “there is a reasonable probability that, had the evidence been disclosed to the defense, the result of the proceeding would have been different. A ‘reasonable probability’ is a probability sufficient to undermine confidence in the outcome.” Ritchie, 480 U.S. at 57, 107 S.Ct. 989 (quotation marks omitted).
We agree with the district court that the Ohio Court of Appeals did not unreasonably apply Brady and its progeny. Benge, No. C-1-98-861, slip op. at 12 (S.D.Ohio July 7, 2004). Because the content of Fuller’s statement and grand jury testimony did not undercut Shields’s trial testimony, such evidence would not have been exculpatory. Furthermore, even if the evidence could be characterized as exculpatory, it was not material because disclosure of the evidence would not have given rise to a reasonable probability that the result of the proceeding would have been different. Even if the version of events contained in Fuller’s affidavit (i.e., that at no time was Benge alone with Fuller and that Benge never said that he had killed Gabbard for her ATM card) had been presented at trial, Fuller’s own prior statements to the contrary could have been used to impeach his new version of the events. We find no reasonable probability that the result of the trial would have been different had such conflicting statements been presented to the jury.
In addition to the foregoing, we note that Fuller’s statement and grand jury testimony were not subject to Brady disclosure for two other reasons. First, Benge knew the essential facts that would have permitted him to take advantage of Fuller’s allegedly exculpatory evidence. United States v. Clark, 928 F.2d 733, 738 (6th Cir.1991) (“No Brady violation exists where a defendant knew or should have known the essential facts permitting him to take advantage of any exculpatory information, or where the evidence is available to defendant from another source.”) (citations and quotation marks omitted).
Benge claims that the issue is not about what he recalled happening at Fuller and Shields’s house, but about what Fuller remembered and would testify to. But Benge heard Shields’s testimony concerning his alleged admission that he murdered Gabbard for her ATM card. If Benge believed that Shields was lying because in fact the two of them were never out of Fuller’s presence, Benge could have called Fuller as a witness to testify about the night in question and thus contradicted Shields. Benge, in other words, knew the essential facts permitting him to take advantage of what Fuller may have been able to say on the subject because he knew that Fuller was in the house that night.
[244]*244Second, the evidence about what Fuller could testify to was not suppressed by the state. See Strickler v. Greene, 527 U.S. 263, 281-82, 119 S.Ct. 1936, 144 L.Ed.2d 286 (1999) (holding that in order to find a Brady violation, “the evidence must have been suppressed by the State, either willfully or inadvertently”). Fuller’s refusal to speak with counsel for Benge did not result from any action by the state, but from Fuller’s dissatisfaction with the way one of Benge’s counsel was representing Fuller in his own unrelated case. No matter how unfortunate for Benge, this was simply not of the prosecutor’s doing.
D. Whether Benge was deprived of the effective assistance of counsel due to his attorney’s alleged conflict of interest arising out of representation of a potential witness in an unrelated matter
In Benge’s state postconviction proceedings, he argued that he was denied the effective assistance of counsel because his trial lawyer represented Fuller in an unrelated drug case. Benge, 1998 WL 204941, at *6-7. Craig Hedric, one of Benge’s two trial counsel, tried to interview Fuller about Benge’s case. Fuller signed an affidavit describing what happened next: “Hedric ‘came to ask me questions about [appellant’s] case. I tried to ask Hedric about my pending drug case, but he only wanted to talk about [appellant’s] case. I refused to talk about [appellant’s] case because I was angry with Hedric for neglecting my case.’ ” Id. at *6 (alterations in original). Benge argued that, as a result of Hedric’s representation of Fuller, He-dric did not learn of allegedly critical information that could have been used to impeach Shields.
1.Ohio Court of Appeals ruling
The Ohio Court of Appeals, the last state court to address this issue on post-conviction review, cited the Supreme Court’s decision in Cuyler v. Sullivan, 446 U.S. 335, 348, 100 S.Ct. 1708, 64 L.Ed.2d 333 (1980), as the controlling authority. In Cuyler, the Court held that “[i]n order to establish a violation of the Sixth Amendment, a defendant who raised no objection at trial must demonstrate that an actual conflict of interest adversely affected his lawyer’s performance.” Id. Benge failed to satisfy that test, according to the Ohio Court of Appeals, because Benge’s and Fuller’s cases “were completely unrelated,” so Hedric did not have a conflict of interest as contemplated in Cuyler. State v. Benge, No. CA97-08-163, 1998, WL 204941, at *7 (Ohio Ct.App.1998). Furthermore, the Ohio court noted that “even if Hedric had spoken with Fuller, Fuller’s testimony would have inculpated rather than exculpated” Benge. Id.
According to the district court, the Ohio Court of Appeals decision was not an unreasonable application of Cuyler. Benge, 312 F.Supp.2d at 991-97. In Smith v. Hofbauer, 312 F.3d 809, 818 (6th Cir.2002), this court clarified that Cuyler applies “only to joint representation and the Supreme Court has yet to extend [that ease’s rule to] reach ... any other type of conflict.” The district court noted that the alleged conflict of interest in this case did not arise out of the joint representation of codefendants in the same trial. Citing Smith, the district court therefore concluded that the Ohio Court of Appeals did not unreasonably apply Cuyler.
We agree with the Ohio Court of Appeals and the district court. Smith forecloses Benge’s argument because there is no clearly established federal law upon which to base the habeas claim in question. That precedent makes clear that Cuyler covers only cases of “joint representation [245]*245at trial.” Smith, 312 F.3d at 815. In the present case there is no dispute that He-dric represented Benge and Fuller in completely unrelated criminal cases. Because Benge cannot cite any clearly established federal law that the Ohio Court of Appeals improperly applied, he fails to meet his burden on this claim.
The district court went on to complete a full Strickland, analysis in addition to concluding that Cuyler did not cover the factual circumstances present in this case. To the extent that Benge could have challenged the district court’s conclusion that trial counsel was not ineffective under a traditional Strickland analysis (as opposed to under Cuyler), he has waived any such claim on appeal. In his main brief, Benge never presents a generic ineffective-assistance-of-counsel claim (as opposed to a Cuyler claim for the alleged conflict of interest), and in his discussion of the claim in his reply brief, he alludes to the presence of Strickland prejudice only in the last line, where he states: “Whether or not prejudice is presumed — which it should be — the record plainly demonstrates that Michael Benge was prejudiced by the representation provided by counsel with divided loyalties.” This single sentence in a reply brief is insufficient to preserve the claim. “[I]t is a settled appellate rule that issues adverted to in a perfunctory manner, unaccompanied by some effort at developed argumentation, are deemed waived.” United States v. Elder, 90 F.3d 1110, 1118 (6th Cir.1996) (quotation marks omitted).
E. Whether the trial court improperly instructed the jury that it could not consider Benge’s guilt as to the charge of voluntary manslaughter if it concluded that he was guilty of aggravated murder
After the trial court instructed the jury on the elements of aggravated murder, it further instructed the jury as follows: “If you find that the State proved beyond a reasonable doubt all of the essential elements of aggravated murder, your verdict must be guilty of that offense and in that event you will not consider any lesser charge.” State v. Benge, 661 N.E.2d at 1024. According to the trial court, the jury could consider the offense of voluntary manslaughter only if the state failed to prove aggravated murder or aggravated robbery. Id.
1. Ohio Supreme Court ruling
Because the Ohio Supreme Court on direct appeal decided this issue on the merits, the Ohio Court of Appeals in the postconviction proceedings declined to consider the claim again, citing the doctrine of res judicata. The Ohio Supreme Court disagreed with the trial court and concluded that “the jury should have been instructed to consider the mitigating evidence to determine whether appellant proved voluntary manslaughter.” Id. at 1025. This was because, under Ohio law, evidence to support a voluntary manslaughter conviction can mitigate a finding of aggravated murder in addition to separately establishing a lesser offense. Id. Despite the trial court’s error, however, the Ohio Supreme Court declined to reverse Benge’s conviction. It determined that reversal would be required only if the error was “plain” because Benge’s counsel had failed to object to the jury instructions. Id. The error was not plain, according to the Ohio Supreme Court, because it did not clearly affect the outcome of the trial. Id. A lack of evidence of provocation persuaded the Court that reversal was not warranted:
The only evidence of provocation was appellant’s testimony that the victim [246]*246tried to run him over and that he became enraged. However, the physical evidence, including the presence of blood and hair on the tire and both sides of the tire track, indicates that appellant may have driven the car through a pool of blood after he beat the victim. The testimony of several state witnesses further supports the state’s version of what occurred rather than appellant’s. Thus, there was sufficient evidence to support appellant’s convictions. Based on the evidence presented, we find no plain error with the court’s instructions. Accordingly, appellant’s first proposition of law is overruled.
Id.
The district court took a slightly different approach, but came to the same conclusion. According to the district court, the Ohio Supreme Court’s treatment of the issue under a plain error standard evidenced the fact that the claim was procedurally defaulted. Benge, 312 F.Supp.2d at 988-91. Benge attempted to excuse his procedural default based on the ineffectiveness of his trial attorneys. This required an analysis under Strickland v. Washington, 466 U.S. 668, 104 S.Ct. 2052, 80 L.Ed.2d 674 (1984), as to whether Benge had demonstrated deficient performance and actual prejudice. The district court concluded that the jury instruction was erroneous, which satisfied the first Strickland prong because defense counsel should have objected. Benge, 312 F.Supp.2d at 988.
With respect to the question of actual prejudice, the district court agreed with the Ohio Supreme Court that the evidence in the case did not support, and in fact contradicted, Benge’s claim that he was provoked into killing Gabbard. Furthermore, the district court concluded that the jury had accepted the government’s version of the events and rejected Benge’s own version, based on the fact that he was convicted of aggravated robbery for taking the bank card and of aggravated murder. The district court therefore concluded that any error of law in the jury instruction did not affect the outcome of the case. Id. at 988-91.
We note as an initial matter that AED-PA’s mandate to defer to state court judgments does not factor into our resolution of this issue. As set forth in Part II.E.l. above, the Ohio Supreme Court analyzed the effect of the unobjected-to jury instruction only in the context of plain-error review, not under the governing — and less burdensome — Strickland standard. Because Benge could have met his burden under Strickland despite not being able to demonstrate plain error, this analysis did not constitute an “adjudication on the merits” of Benge’s ineffective-assistance-of-counsel claim. See Danner v. Motley, 448 F.3d 372, 376 (6th Cir.2006) (“The AEDPA standard of review applies only to ‘any claim that was adjudicated on the merits in State court proceedings.’ ” (quoting 28 U.S.C. § 2254(d))).
The earlier judgment of the Ohio Court of Appeals was also insufficient to warrant AEDPA deference. Although that court applied the proper standard, it never reached the now-dispositive prejudice prong, instead denying Benge’s claim on the ground that his counsel had not been deficient. State v. Benge, No. CA 93-06-116, 1994 WL 673126, at *21 (Ohio Ct.App. Dec. 5,1994) (“[TJhere is no demonstration that trial counsel’s performance was deficient or that were it not for counsel’s alleged errors, the result of the trial or the sentencing decision would have been different.”). In sum, there was no reasoned adjudication of Benge’s ineffective-assis[247]*247tance-of counsel claim on the merits by the Ohio state courts. AEDPA is therefore inapplicable, making our review de novo. Danner, 448 F.3d at 376 (reviewing Dan-ner’s Sixth Amendment claim de novo “because no state court reviewed his constitutional challenge on the merits”).
We nonetheless concur in the result reached by the district court. In attempting to excuse his procedural default, Benge must demonstrate “that there was cause for the default and prejudice resulting from the default, or that a miscarriage of justice will result from enforcing the procedural default in the petitioner’s case.” Lundgren v. Mitchell, 440 F.3d 754, 763 (6th Cir.2006). Because we conclude that Benge has failed to show the actual prejudice necessary to excuse his procedural default, we will assume without deciding that the district court correctly determined that the first prong of Strickland was satisfied.
Benge argues, however, that prejudice under Strickland’s second prong should be presumed because defense counsel entirely failed to subject the prosecution’s case to meaningful adversarial testing, relying on the Supreme Court’s decision in United States v. Cronic, 466 U.S. 648, 659, 104 S.Ct. 2039, 80 L.Ed.2d 657 (1984). But the Supreme Court has clarified that the Cronic presumption applies only where defense counsel completely or entirely fails to oppose the prosecution throughout the guilt or penalty phase as a whole. Bell v. Cone, 535 U.S. 685, 697, 122 S.Ct. 1843, 152 L.Ed.2d 914 (2002) (interpreting the Cronic presumption of prejudice for failure to test the government’s case as covering only the “complete” failure of defense counsel to perform during the “proceeding as a whole,” not a failure at “specific points”). Here, counsel’s failure to object to the erroneous jury instruction, no matter how professionally unreasonable, was not a complete failure to provide a defense. The presumption of prejudice therefore does not apply, so Benge must demonstrate that he suffered from actual prejudice.
Under Strickland, in order to show actual prejudice, “[t]he defendant must show that there is a reasonable probability that, but for counsel’s unprofessional errors, the result of the proceeding would have been different. A reasonable probability is a probability sufficient to undermine confidence in the outcome.” Strickland, 466 U.S. at 694, 104 S.Ct. 2052. In terms of this case, then, the issue is whether, but for defense counsel’s failure to object to the erroneous jury instruction, there is a reasonable probability that the outcome of Benge’s case would have been different.
Benge’s voluntary-manslaughter alternative to the aggravated-murder charge hinged on a showing that he was “under the influence of sudden passion or in a sudden fit of rage, either of which is brought on by serious provocation occasioned by the victim that is reasonably sufficient to incite the person into using deadly force” at the time he murdered Gabbard. See Ohio Rev.Code Ann. § 2903.03(A). The Ohio Supreme Court has held that this is the defendant’s burden, and the showing must be made by a preponderance of the evidence. State v. Rhodes, 63 Ohio St.3d 613, 590 N.E.2d 261, 265 (Ohio 1992) (placing on the defendant, in a trial for aggravated murder, the burden of proving by a preponderance of the evidence that the requisite state of passion or rage was present at the time of the murder in order for the defendant to be convicted of voluntary manslaughter rather than aggravated murder).
In attempting to meet his burden, Benge testified that he became enraged when Gabbard tried to run him over. This [248]*248testimony constituted the entirety of the evidence supporting his affirmative provocation defense. But other portions of Benge’s testimony, as well as additional evidence introduced by the government, seriously undercut his version of the events. When initially questioned by the police, for example, Benge concocted a cover story of how two unidentified black men had murdered Gabbard. In addition, Shields testified that Benge had told her on the night of the murder that attaining Gabbard’s ATM card was his motivation for killing her. Benge attempted to undermine Shields’s testimony at trial, testifying that he had been in possession of Gabbard’s ATM card before the murder and that he had never robbed her of the card. But the jury necessarily disbelieved this testimony, because it would not and could not have found Benge guilty of aggravated robbery had it found that Benge possessed the ATM card prior to the murder. Finally, there was the physical evidence of a pool of blood on the ground with a tire track running through it, as well as blood in the tire treads. This evidence refutes the sequence of events Benge described — that Gabbard tried to run him over, the car got stuck in the mud, and then he killed her.
The common definition of the phrase “preponderance of the evidence,” as found in law treatises and standard jury instructions, is evidence that is of greater weight, on balance, than that offered in opposition to it. See, e.g., 32A C.J.S. Evidence § 1312 (2006). In light of the evidence presented both in favor of and against Benge’s claim of provocation, we see no reasonable probability that a juror would have found that Benge had proved serious provocation by a preponderance of the evidence. See Strickland, 466 U.S. at 695, 104 S.Ct. 2052 (“The assessment of prejudice should proceed on the assumption that the decisionmaker is reasonably, conscientiously, and impartially applying the standards that govern the decision.”). We are thus persuaded that there is no reasonable probability that a juror would have accepted Benge’s voluntary-manslaughter defense, even if the jury had been properly instructed. This being so, defense counsel’s alleged ineffectiveness cannot meet the cause-and-prejudice standard as necessary to excuse Benge’s procedural default.
The dissent correctly notes that the erroneous jury instruction effectively foreclosed the possibility that the jury could have found Benge guilty of the robbery but not guilty of the murder. Dissenting Op. at 251. We also recognize, as the dissent emphasizes and as the district court itself acknowledged, that “[a] conviction for aggravated robbery does not as a matter of law preclude an affirmative defense of provocation with regard to a related murder charge.” Id.; Benge, 312 F.Supp.2d at 990 (“In theory, petitioner could have been found guilty of aggravated robbery without having been found guilty of aggravated murder.”). But the dissent fails to persuade us that there is a reasonable probability that a properly instructed jury would have concluded that Benge met this affirmative burden. Instead, the dissent simply notes that
[biased on the evidence presented in this case, Benge could have had no plan to rob or murder Gabbard when they got in the car together. He could have then been provoked by her fighting with him, and attacked her in response, consistent with his testimony at trial. Upon concluding his attack on Gabbard, it could have occurred to him to take the ATM card from her before disposing of her body in the river.
Dissenting Op. at 251 (emphasis added).
[249]*249What Benge could have done, however, is irrelevant at this stage in the proceedings. We must be able to say that a reasonable probability exists that a properly instructed jury would have concluded that Benge had shown provocation by a preponderance of the evidence. Given that Benge’s provocation defense rested almost exclusively on his own extremely dubious and at times inconsistent testimony, we are unable to so conclude.
Both Benge and the dissent attempt to overcome the foregoing analysis by relying on the case of Barker v. Yukins, 199 F.3d 867, 874 (6th Cir.1999), for the proposition that the jury, not a reviewing court, is the proper decisionmaker on the question of whether Benge met his burden of proving adequate provocation. In Barker, the defendant went to trial on a charge of first-degree murder. Id. at 869. She alleged that the killing was in self-defense because the victim, an 81-year old man, was attempting to rape her. Id. The trial court refused to specifically instruct the jury that Barker was entitled to use deadly force in self-defense in order to resist an imminent rape, instead delivering the general self-defense instruction permitting the use of lethal force if the victim honestly believed that she was “in danger of death or serious bodily injury.” Id. at 870. On direct appeal, the Michigan Supreme Court found that the trial court erred in refusing to give the specific instruction, but that the error was harmless because no reasonable juror would have believed Barker’s self-defense claim in light of the fact that the alleged perpetrator was “enfeebled” and that Barker had delivered 10 blows to the victim’s head and stabbed him 32 times. Id.
This court in Barker had to decide “whether the Michigan Supreme Court’s finding of harmless error involved an unreasonable application of federal law.” Id. at 872. Essentially two reasons were given in support of the conclusion that the state court had unreasonably applied federal law in its harmless-error analysis. First, this court stated that the general self-defense instruction left the door open for the jury to find that Barker understood that she was going to be the victim of an imminent rape, but that she was not about to be subjected to death or serious bodily injury. Id. at 873. That possibility caused this court to have “grave doubt as to whether the erroneous jury instruction created a substantial and injurious influence on the verdict.” Id. at 874. Furthermore, this court went on to state that the Michigan Supreme Court’s harmless-error analysis “improperly invaded the province of the jury” in determining that “no reasonable juror could have believed that the force used by Barker was necessary to prevent rape by an 81-year old ‘enfeebled’ man.” Id. According to this court, the proper role of a judge in reviewing a conviction is not “to stand in the place of the jury, weighing competing evidence and deciding that some evidence is more believable than others.” Id. at 874-75. This court thus concluded that the Michigan Supreme Court unreasonably applied federal law. Id. at 876.
Barker does not foreclose our analysis as set forth above, however, because it arose in a completely different context. This court in Barker was evaluating a harmless-error analysis undertaken by a state court on direct review. Here we are not reviewing the merits of the underlying claim, but are instead inquiring whether the alleged ineffective assistance of Benge’s counsel in failing to object excuses the procedural default. In evaluating claims of ineffective assistance of counsel, this court must typically assess the evidence introduced at trial in order to determine whether the defendant was [250]*250prejudiced. See, e.g., Strickland, 466 U.S. at 695, 104 S.Ct. 2052 (“In making this determination [of whether the alleged ineffectiveness of counsel prejudiced the defendant], a court hearing an ineffectiveness claim must consider the totality of the evidence before the judge or jury.”); Hodge v. Hurley, 426 F.3d 368, 376 n. 17 (6th Cir.2005) (“[T]he prejudice determination is necessarily affected by the quantity and quality of other evidence against the defendant.”). We see nothing in Barker to preclude our review of the evidence in assessing whether the ineffective-assistance claim excuses a procedural default. Benge’s reliance on that case is therefore unavailing.
Because we conclude that Benge has failed to demonstrate that the ineffectiveness of his counsel resulted in actual prejudice, the procedural default of his jury-instruction claim is not excused. We therefore concur in the district court’s analysis on this issue.
Finally, we note that evidence of arbitrariness in the enforcement of the death penalty in this country, no matter how compelling, does not afford Benge a basis for habeas relief under existing Supreme Court jurisprudence. Instead, as the dissent concedes, arbitrariness-based arguments are and will remain “only [ ] observations without the force of law” until the Supreme Court says otherwise. Dissenting Op. at 258. We accordingly see no need to engage in a further policy debate in the context of the present case.
III. CONCLUSION
For all of the reasons set forth above, as well as for the reasons set forth in the opinions of the district court entered on March 31, 2004 and July 7, 2004, we AFFIRM the judgment of the district court.