Tеxas death row inmate Ricardo Ortiz (“Ortiz”) appeals the district court’s denial of his 28 U.S.C. § 2254 habeas corpus petition in which he claimed that the Texas retaliation statute was an unconstitutional ex post facto law when applied to him. He also moves for a certificate of appealability (“COA”) to appeal two additional issues, arguing that reasonable jurists would find debatable whether the trial court improperly excluded a veniremember from jury service because of her views regarding the death penalty and whether the trial court improperly instructed the jury on the req *495 uisite burden of proof for imposition of the death penalty.
I
On August 6,1997, Ortiz was arrested in El Paso, Texas, for violating the terms of his parole. He told arresting officers that, in exchange for his release from custody, he would give them information about a series of unsolved bank robberies. The officers contacted the F.B.I., who had been investigating the bank robberies and already had suspected Gerardo Garcia (“Garcia”) to be the main bank robber. The F.B.I. did not yet know the identity of the get-away driver, but after hearing that Ortiz had special information about the robberies, they suspected Ortiz might be the man for whom they were looking. By the time the F.B.I. arranged to speak with him, however, Ortiz had changed his mind and refused to talk. In light of Ortiz’s refusal, the F.B.I. scheduled an interview with Garcia, who was already in the custody of El Paso police, hoping that Garcia would name Ortiz as the get-away driver.
When Garcia, too, refused to talk, the F.B.I. concocted a plan that it hoped would convince Ortiz to implicate Garcia, and vice versa, in the bank robberies. Agents scheduled a second interview with Garcia and arranged for Ortiz to be brought past the interrogation room so that the two men could see each other and make eye contact. The F.B.I. hoped that each would assume his accomplice was cooperating with investigators and would do the same. When neither suspect was forthcoming with incriminating information, however, agents drafted a federal arrest warrant for Garcia on bank robbery charges and attached a probable cause statement that falsely mentioned Ortiz as one of the individuals implicating him. The F.B.I. showed Ortiz the probable cause statement and warned Ortiz that Garcia would be shown the warrant and would learn that Ortiz had “snitched him off,” implying that Garcia might then retaliate by implicating Ortiz.
When neither suspect would talk about the robberies, Ortiz and Garcia were placed in the same tank in the El Paso Detention Center. This unit was reserved for members of the Texas Syndicate, an aggressive and violent gang notorious for its rigid hierarchy and ruthless intolerance of disloyalty. Ortiz was a high-ranking officer of the Texas Syndicate and “tank boss” of this unit.
On August 19, 1997, Garcia was found dead in the bed of his jail cell. An autopsy revealed that Garcia died of a heroin overdose, one so high that it was three times greater than the amount sufficient to cause death. There were fresh needle marks and bruises on his left arm, but no needle track marks, indicating that Garcia probably was not a heroin addict. Prison witnesses revealed that Ortiz had obtained heroin the evening before Garcia was found dead and, that night, had injected Garcia with the syringe. Ortiz’s cellmate revealed that Ortiz had told him that Garcia “must die” for implicating him in the bank robberies that he and Garcia had committed together.
Ortiz was indicted by a Texas grand jury with “intentionally caus[ing] the death of an individual, namely, Gerardo Garciа, by injecting Gerardo Garcia with heroin ... then and there in the course of committing and attempting to commit the offense of retaliation against Gerardo Garcia.” The retaliation component elevated Garcia’s murder to a capital offense. See Tex. Penal Code § 19.03(a)(2) (Vernon 1997). 1
*496
On June 16, 1999, the jury found Ortiz guilty of capital murder. During the punishment phase, Ortiz did not present any mitigating evidence. Ortiz was sentenced to death, and his conviction and sentence were affirmed on direct appeal.
Ortiz v. State,
Ortiz timely filed a state petition for a writ of habeas corpus. Deciding that a hearing was unnecessary, the state habeas court entered findings of fact and conclusions of law recommending that аll relief be denied. The Texas Court of Criminal Appeals (“TCCA”) denied relief in an unpublished order based on those findings and conclusions and its own review of the record.
Ex parte Ortiz,
No. 54,488-01 (Tex.Crim.App.2003) (per curiam) (unpublished order). Ortiz filed a federal habeas petition asserting seven claims for relief, including the three presented in the instant appeal and application for COA. The district court denied Ortiz’s claims but granted a COA for us to decide whether the Texas retaliation statute is an unconstitutional
ex post facto
law as applied to Ortiz.
Ortiz v. Livingston,
II
We first address Ortiz’s
ex post facto
claim. We review the district court’s findings of fact for clear error and reviеw its conclusions of law
de novo,
applying the same standard of review to the state court’s decision as the district court.
Thompson v. Cain,
(1) resulted in a decision that was contrary to, or involved an unreasonable application of, clearly established Federal law, as determined by the Supreme Court of the United States; or
(2) resulted in a decision that was based on an unreasonable determination of the facts in light of the evidence presented in the State court proceeding.
28 U.S.C. § 2254(d).
Whether Texas’s retaliation statute violates the
Ex Post Facto
Clause, U.S. CONST. art. I, § 10 (“No State shall ... pass any ... ex post facto Law ... ”), when applied to Ortiz is a question of law and, accordingly, is governed by section 2254(d)(1).
See Martin v. Cain,
*497 Ortiz’s ex post facto claim concerns the change in the crime of “retaliation” between the time of Garcia’s murder and the time Ortiz was tried. On the day of Garcia’s murder, August 19, 1997, Texas defined the crime of “retaliation” as “intentionally or knowingly harm[ing] or threaten[ing] to harm another by an unlawful act: in retaliation for or on account of the service of another as a public servant, witness, prospective witness, informant, or a person who has reported or who the actor knows intends to report the occurrence of a crime.” Tex. Penal Code § 36.06(a)(1) (effective Sept. 1, 1994 through Sept. 1, 1997) (emphasis added). Texas amended its retaliation statute to take effect on September 1, 1997, only a few days after Garcia’s alleged murder. In contrast to the pre-amendment statute which specified only “service,” the amended statute criminalizes harming or threatening to harm another for his “service or status” as one of those named persons. Id. § 36.06(a)(1) (effective Sept. 1, 1997) (emphasis added). 2 The indictment did not include a particular version of the retaliation statute; the document simply charged Ortiz with murder in the course of retaliation. The trial judge, though, instructed the jury with the amended definition of retaliation rather than the definition in effect at the time of the offense. 3
Although he did not object to the charge during trial, Ortiz challenged the jury instruction on direct appeal, arguing that jury instructions that included the amended version of the statute violated the
Ex Post Facto
Clause. The TCCA rejected Ortiz’s claim on two grounds. First, the TCCA concluded that the
Ex Post Facto
Clause “is directed at the Legislature, not the courts,” and, as a result, “an ex post facto problem does not arise from a trial court’s erroneous retroactive application of a statute, but only if the statute itself has retroactive effect.”
Ortiz,
The evidence supports a conclusion that Ortiz murdered Garcia due to either his status or his service as a prospective witness .... With the other options in the statute — public servant, witness, and informant — there is a clear difference between that person’s status versus his service. But with a “prospective witness,” the line is blurred, since the word “prospective” denоtes a future event. There is little difference between a prospective witness’ status and his service. As a result, we cannot conclude that Ortiz was egregiously harmed by the erroneous charge.
Id. at 92.
On one occasion, in a case cited by neither party, the Supreme Court was presented with a question of whether jury instructions violated the
Ex Post Facto
Clause.
4
See Splawn v. California,
*499
Even if we were to entertain Ortiz’s
ex post facto
challenge, we still would conclude that he is not entitled to habeas relief. Under the
Ex Post Facto
Clause, Ortiz must prove that the law, retroactively applied to him, caused him some disadvantage.
See Weaver v. Graham,
The pre-amendment version of the statute criminalized harming another on account of his service as a public servant, witness, prospective witness, informant, or a person who has reportеd or who the actor knows intends to report the occurrence of a crime. The amended statute criminalizes harming another on account of his service or status as one of these named persons. Ortiz was charged only with retaliating against “a prospective witness” or a “person who has reported or who the actor knows intends to report the occurrence of a crime.” He was not charged with committing retaliation against those other named persons&emdash;“public servant,” “witness,” or “informant.”
Ortiz argues that rendering “service” requires a prospective witness to take steps toward testifying and that Garcia never performed any “service” because he never provided information to the authorities. Any distinction, however, does not turn on the definitions of “status” and “service,” but rather on the definition of “prospective witness.” As the TCCA explained;
With the other options in the statute&emdash; public servant, witness, and informant&emdash; there is a clear difference between that person’s status versus his service. But with a “prospective witness,” the line is blurred, since the word “prospective” denotes a future event.
Ortiz,
In sum, the Supreme Court has never held jury instructions to be unconstitutional under the Ex Post Facto Clause. Even if there were such a decision, Ortiz’s ex post facto claim cannot prevail because the amended version of Texas’s retaliation statute did not change the definition of retaliation as applied to Ortiz. Accordingly, it was not unreasonable for the TCCA to deny Ortiz’s claim.
Ill
We next address Ortiz’s petition for a COA. We grant a COA only when the petitioner has made “a substantial showing of the denial of a constitutional right.” 28 U.S.C. § 2253(c)(2). This standard requires Ortiz to demonstrate that “jurists of reason could disagree with the district court’s resolution of his constitutional claims or that jurists could conclude that the issues presented are adequate to deserve encouragement to proceed further.”
Miller-El v. Cockrell,
A
First, Ortiz petitions for a COA to appeal the district court’s denial of his claim that the trial court erred in granting the State’s challenge for cause to Anna Doporto (“Doporto”), a member of the ve-nire, because she vоiced opposition to the death penalty.
6
Ortiz argues that Dopor-to’s exclusion from the jury violated his Sixth and Fourteenth Amendment rights as set out by the
Witherspoon-Witt
rule.
See Wainwright v. Witt,
During voir dire, but prior to individual questioning on this point, the trial court spoke to the entire venire, including Doporto, saying:
I am now going to ask you some questions about your convictions regarding the death penalty. Be assured that I am not now assuming that you will find the defendant guilty of capital murder or of any other crime in this case. Nevertheless, it is necessary to learn your state of mind about capital punishment in general, to determine whether you have an open mind as regards [to] what might be a just and proper sentence in a capital case if the defendant in that case is found guilty as charged.
So I am asking about your state of mind regarding capital murder in general. I am not asking in this next question what you think would be a just penalty in this or any particular case. I’m not at this time even asking you about your opinion as regards the death penalty in a retaliation capital murder case. And I am most especially not asking what you might think would be a just verdict in this case — in this particulаr case. I am asking, rather, whether for religious or philosophical or any other reason you believe that the death penalty should never be inflicted in any case, regardless of what the evidence might be.
In answering this next question, keep in mind that the circumstances and motives for the commission of crimes, including capital murder, are unlimited. Place a check mark by your answer, yes or no. Do you have conscientious scruples in regard to the infliction of death for a person convicted of capital murder? Yes or no?
If you answered the proceeding [sic] question yes, come up to the bench now.
Doporto was one of several venire-members who identified themselves as having significant conscientious scruples against the death penalty. She approached the bench, and the following exchange ensued:
Ms. Doporto: Number 88, Anna Dopor-to. I have seen other murder cases and have agreed with the death penalty, but I don’t feel I could bring a death penalty for somebody, to put that pressure on me.
The Court: Ma’am it’s not a question right now of how you feel about your serving as a juror. Right now, are you opposed to the death penalty in all cases?
Ms. Doporto: No, sir.
The Court: Could you ever, sitting as a juror, no matter — no matter what the evidence showed, vote to inflict the death penalty?
Ms. Doporto: No, sir.
The Court: Anybody want to ask a further question[?]
*502 Neither the Stаte nor the defense accepted the trial court’s invitation to ask additional questions. The State then moved to exclude Doporto for cause, the judge granted the State’s motion, Ortiz’s counsel objected, and the judge overruled the objection.
On direct appeal, the TCCA rejected Ortiz’s claim that Doporto had been improperly excluded for cause because of her views on capital punishment. Applying the Wibherspoon-Witt standard, the TCCA concluded:
The trial court’s question to Deporto [sic], asking whether she could vote to inflict the death penalty, was not clearly worded, and any answer to that question, in isolation, would be inconclusive on the question of whether a prоspective juror is challengeable under Witt. However, the trial court had earlier phrased the issue clearly and correctly ..., and the question directed specifically at De-porto [sic] was asked in the context of a juror who had already expressed doubt about her ability to personally assess the death penalty. A prospective juror is challengeable for cause under Witt if she could never personally impose the death penalty, regardless of the facts of the case, even though she might support imposition of the death penalty in the abstract or if someone else imposed it. Although the trial court’s question to Deportо [sic] was ambiguous, the record in this case was sufficient for the trial court to believe that Deporto [sic] could never personally vote in such a manner that the death penalty would be assessed. The trial court did not abuse its discretion in granting the State’s challenge for cause.
Ortiz,
On federal habeas review, the district court also denied relief out of deference to the state trial court’s determination that Doporto was unwilling to impose the death penalty even when the law or facts called for it. The court explained: “whether a particular member of the jury pool is or is not biased and therefore properly seated on the jury is a quеstion of fact based on the trial judge’s on-the-spot assessment of credibility and demeanor,” and the TCCA’s “decision did not represent an unreasonable determination of the facts in light of the evidence before it.”
Ortiz,
On this record, we do not find the district court’s conclusion to be debatable or wrong. The TCCA identified and applied the correct
Witherspoon-Witt
rule and deferred to the trial court’s assessment of Doporto’s inability to apply the law of capital punishment. The TCCA’s decision to defer to the trial court is not an unreasonable application of law, as the Supreme Court has explicitly held that “[s]uch determinations [are] entitled to deference even on direct review; ‘the respect paid such findings in a habeas proceeding certainly should be no less.’ ”
Witt,
Ortiz’s argument that the colloquy between the trial judge and Doporto was too ambiguous to support the trial court’s decision is unavailing. Doporto was asked if she could “ever, sitting as a juror, no matter — no matter what the evidence showed, vote to inflict the death penalty,” and she replied “No, sir.” Her answer supports the trial court’s finding of “substantial impairment” under
Witt.
Even though Doporto gave conflicting signals of her ability to serve on the jury given her opposition to capital punishment — she seemed to both “agree[] with the death penalty” in some cases but did not “fеel” that she could impose it herself — ambiguity alone does not undermine the trial court’s decision to exclude her. Rather, “the trial court, aided as it undoubtedly [is]
*503
by its assessment of [the veniremember’s] demeanor, [is] entitled to resolve [ambiguity] in favor of the State.”
Uttecht v. Brown,
— U.S. -,
We also reject Ortiz’s contention that the wording of the questions asked Dopor-to during
voir dire
did not correctly state the relevant legal standard under
Witt.
Ortiz takes issue with the fact that the trial court, at one point, asked the entire venire: “do you have conscientious scruples in regard to the death penalty?” Under
Witherspoon,
this is an impermissible reason for excluding veniremembers from the jury.
Clearly established law, however, does not mandate precise
voir dire
questions, as “determinations of juror bias cannot be reduced to question-and-answer sessions which obtain results in the manner of a catechism.”
Witt,
There are certain rules of law that the Court — that means the Judge — instructs every juror to obey in every criminal case. To be quаlified to serve as a juror, a person must be able to obey those instructions. Now, a person may not be able to obey the instruction because he has such a deep-seated disagreement with the law or for any other reason. [But] the jury has to be able to accept the law and say, All right, I don’t like it, but I can rule according to it, judge the case according to it. Or you can say, I don’t like it so much there’s no way I can follow that law.
The trial court also explained the eight circumstances under which murder becomes capital murder in Texas, and detailed the “special issues” questions that would be asked during sentencing if the jury were to find the defendant guilty. It was in this context — after being instructed on the importance of separating one’s personal beliefs from applying the law and after being told the mitigation facts that must be found during capital sentencing— that Doporto was asked whether she could ever vote for the death penalty. Like the veniremember in
Darden,
Doporto “was present throughout an entire series of questions that made the purpose and meaning of the
Witt
inquiry absolutely clear,”
B
Second, Ortiz petitions for a COA to appeal the district court’s denial of his claim thаt the Supreme Court’s decisions in
Apprendi v. New Jersey,
Whether, taking into consideration all of the evidence, including the circumstances of the offense, the defendant’s character and background, and the personal moral culpability of the defendant, there is a sufficient mitigating circumstance or circumstances to warrant that a sentence of life imprisonment without parole rather than a death sentence be imposed.
See Tex.Code Crim. Pkoc. Ann. art. 37.071 § 2(e) (Vernon 1999). Texas law does not assign a burden of proof to the mitigation question, and Ortiz asserts that the lack of a beyond-a-reasonable-doubt instruction is constitutional error.
The TCCA rejected Ortiz’s claim based on
Williams v. State,
We decided this question in
Scheanette v. Quarterman,
IV
For the foregoing reasons, we AFFIRM the judgment of the district court DENYING habeas relief, and we DENY the application for a COA.
Notes
. Texas Penal Code § 19.03(a)(2) defined capital murder as murder and "intentionally *496 commit[ting] the murder in. the course of committing or attempting to commit kidnapping, burglary, robbery, aggravated sexual assault, arson, obstruction or retaliation, or ter-roristic threat ...."
. The amended statute in full reads: "intentionally or knowingly harm[ing] or threaten[ing] to harm another by an unlawful act: (1) in retaliation for or on account of the service or status of another as a(A) public servant, witness, prospective witness, or informant; or (B) person who has reported or who the actor knows intends to report the occurrence of a crime ....” Tex. Penal Code § 36.06(a)(1) (effective Sept. 1, 1997) (emphasis added).
. At trial, the jury was instructed:
As to the law of capital murder and murder, our law provides that a person commits murder when he intentionally or knowingly causes the death of an individuаl. A person commits capital murder when such person intentionally commits the murder the course of committing or attempting to commit the offense of retaliation.
As to the law of retaliation, our law provides that a person commits an offense if he intentionally or knowingly threatens to harm another by an unlawful act in retaliation for, or- on account of, the service or status of another, A, as a prospective witness; or B, a person who has reported or who the actor knows intends to report the occurrence of a crime, (emphasis added).
. We note that challenges to the accuracy of jury instructions generally are raised as due process violations.
See e.g., Middleton v. McNeil,
. We reach no conclusion as to whether the TCCA erred in holding that "an
ex post facto
problem does not arise from a trial court's erroneous retroactive application of a statute, but [rather] only if the statute itself has retroactive effect." We note, however, that the Supreme Court has entertained
Ex Post Facto
Clause challenges premised on a trial court's retroactive application of a statute to acts completed before the statute's effective date.
See Weaver v. Graham,
. In the district court, Ortiz claimed that the trial court erred in excluding eighteen other veniremembers for cause. The district court found that this claim was procedurally defaulted in state court for failure to object to each veniremember’s exclusion.
See Ortiz v. Livingston,
. We note, however, that "[t]he need to defer to the trial court's ability to perceive jurors’ demeanor does not foreclose the possibility that a reviewing court may reverse the trial court’s decision where the record discloses
no basis
for a finding of substantial impairment.”
Uttecht,
. Ortiz contends that Doporto reasonably could have understood the trial judge's question to have meant whether she would be willing to vоte for the death penalty "no matter what the evidence showed” or, in other words, whether she would always vote for the death penalty. Not only is this interpretation far-fetched, but as explained below, the entire colloquy, viewed as a whole, reveals that a juror must have understood the opposite— whether Doporto would have been unwilling *504 to vote for the death penalty, even if it were mandated by the facts.
. Also probative is Ortiz’s counsel's decision not to question Doporto, which deprived reviewing courts of additional factual findings that may have further explained the trial court’s decision or indicated that Doporto was not substantially impaired.
Uttecht,
