UNITED STATES COURT OF APPEALS 

FOR THE TENTH CIRCUIT 

______________________________________________ 

MARIO CHAVEZ, 

 Petitioner - Appellant, 

v. 

VINCENT HORTON, Warden; NEW 

MEXICO ATTORNEY GENERAL, 

 Respondents - Appellees. 

No. 23-2084 

(D.C. No. 1:19-CV-01151-KWR-LF) 

(D. N.M.)

______________________________________________ 

ORDER

______________________________________________ 

Before BACHARACH, BALDOCK, and MORITZ, Circuit Judges. 

______________________________________________ 

This case grew out of a fatal shooting in New Mexico. The shooting 

led to state-court convictions of Mario Chavez for first-degree murder, 

armed robbery in the second degree, and tampering with evidence. 

Following the convictions, Mr. Chavez unsuccessfully appealed and sought 

habeas relief in both state court and federal district court. He wants to 

appeal the rulings in federal court on his claims involving 

 violation of the Confrontation Clause, 

 trial errors, and 

 ineffective assistance of counsel. 

FILED 

United States Court of Appeals 

Tenth Circuit 

May 24, 2024

Christopher M. Wolpert 

Clerk of Court

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To appeal, however, he needs a certificate of appealability. 28 U.S.C. 

§ 2253(c)(1)(A). We decline to issue the certificate. 

1. The availability of a certificate is affected by statutory 

limitations on habeas relief. 

 To justify a certificate, Mr. Chavez must “[make] a substantial 

showing of the denial of a constitutional right.” 28 U.S.C. § 2253(c)(2). 

When a district court rejects a claim on the merits, the petitioner “must 

demonstrate that reasonable jurists would find the district court’s 

assessment of the constitutional claims debatable or wrong.” Slack v. 

McDaniel, 529 U.S. 473, 484 (2000). We apply this standard against the 

backdrop of Mr. Chavez’s underlying burden to justify habeas relief. See 

Miller-El v. Cockrell, 537 U.S. 322, 336 (2003) (stating that when deciding 

whether to grant a certificate of appealability, the court “look[s] to the 

District Court’s application of [the Antiterrorism and Effective Death 

Penalty Act] to petitioner’s constitutional claims and ask[s] whether that 

resolution was debatable amongst jurists of reason”). 

This burden is heavy when the state court has rejected a 

constitutional claim on the merits. In that circumstance, federal law 

requires the petitioner to show that the state court’s decision was contrary 

to, or an unreasonable application of, Supreme Court precedent. 28 U.S.C. 

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§ 2254(d)(1).1 A decision is considered unreasonable only if every 

fair-minded jurist would have “‘reach[ed] a different conclusion.’” Andrew 

v. White, 62 F.4th 1299, 1317 (10th Cir. 2023) (quoting Brown v. 

Davenport, 596 U.S. 118, 144 (2022)), pet. for cert. docketed (U.S. 

Jan. 25, 2024) (No. 23-6573). But these statutory limitations apply only 

when the state court had reached the merits of the federal claim. See 

Gipson v. Jordan, 376 F.3d 1193, 1196 (10th Cir. 2004). 

Mr. Chavez argues that the federal district court shouldn’t have 

applied these limitations because the state court hadn’t considered the 

merits of his constitutional claims. For this argument, Mr. Chavez bears 

the burden. See Simpson v. Carpenter, 912 F.3d 542, 583 (10th Cir. 2018) 

(“The petitioner bears the burden of showing a claim was not adjudicated 

on the merits in state court.”).

But in federal district court, Mr. Chavez hadn’t made this argument 

in his habeas petition or his supplements to the petition. He instead waited 

until his reply brief to argue that the state court had overlooked the merits 

of his constitutional claims. The federal district court concluded that the 

reply brief had been too late for Mr. Chavez to make this argument. See, 

1

 A petitioner may also obtain habeas relief by demonstrating that a 

state court’s decision on a federal claim “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)(2). But Mr. Chavez does not point 

to an unreasonable factual determination in state court. 

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e.g., United States v. Beebe, 807 F. Supp. 2d 1045, 1054 (D. N.M. 2011) 

(stating that the District of New Mexico “normally does not entertain 

arguments raised for the first time in a reply brief”). If we were to 

entertain an appeal on this issue, Mr. Chavez would bear the burden of 

showing that the federal district court had abused its discretion in deciding 

that the reply brief was too late. See United States v. Coyote, 963 F.2d 

1328, 1332 (10th Cir. 1992) (reviewing a decision on waiver for an abuse 

of discretion). 

Mr. Chavez doesn’t deny that he needed to make this argument 

before his reply brief. But he insists that he raised the argument in his 

habeas petition when he referred to state-court documents and recounted 

the procedural history. The federal district court rejected Mr. Chavez’s 

reliance on state-court documents, reasoning that he had referred to 

hundreds of pages rather than point to specific documents. Mr. Chavez 

questions this reasoning, but the federal district court had no obligation to 

scour the state-court record in order to find where the petitioner had raised 

this argument. See SIL-FLO, Inc. v. SFHC, Inc., 917 F.2d 1507, 1514 (10th 

Cir. 1990) (stating that we didn’t need to scour a voluminous transcript 

when the appellant failed to give specific record cites). And Mr. Chavez’s 

recitation of the procedural history didn’t constitute a separate argument. 

Apart from these procedural shortcomings, however, Mr. Chavez 

hasn’t shown a failure of the state court to decide the merits of his claims. 

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Even when a state court doesn’t mention the federal basis for a claim, we 

presume that the court decided the merits of the federal claim. See Simpson 

v. Carpenter, 912 F.3d 542, 583 (10th Cir. 2018). And Mr. Chavez hasn’t 

made a colorable showing to rebut that presumption.2 Mr. Chavez thus 

hasn’t shown that reasonable jurists could debate the district court’s ruling 

on waiver or its application of the statutory limitations on habeas relief. 

2. Mr. Chavez has not presented a reasonably debatable habeas 

claim involving violation of the Confrontation Clause or a related 

claim of ineffective assistance. 

Mr. Chavez claims that the state court committed two violations of 

the Sixth Amendment’s Confrontation Clause. The first claim grew out of 

an alleged conversation hours after the murder. At that time, a codefendant 

(Mr. Eloy Montano) allegedly told his wife that he thought he had been set 

up by Mr. Chavez. Mr. Montano didn’t testify at the trial, but the wife was 

allowed to testify about this statement. The second claim involves the 

introduction of Mr. Montano’s entire interrogation by the police.

2

 In Mr. Chavez’s state habeas proceedings, the state supreme court 

issued summary orders denying certiorari. But we presume that the court 

rested on the same reasons given by the state district court. See Ylst v. 

Nunnemaker, 501 U.S. 797, 802–04 (1991) (presuming that “[w]here there 

has been one reasoned state judgment rejecting a federal claim, later 

unexplained orders upholding that judgment or rejecting the same claim 

rest upon the same ground”). 

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2.1. Mr. Chavez doesn’t present a reasonably debatable habeas claim 

involving violation of the Confrontation Clause. 

The Confrontation Clause would be violated only if Mr. Montano’s 

out-of-court statements had been “testimonial.” Crawford v. Washington, 

541 U.S. 36, 59, 68 (2004). And even if the statements could be 

characterized as testimonial, Mr. Chavez would need to show that a 

Supreme Court opinion had clearly established this characterization. See 

28 U.S.C. § 2254(d)(1); see also House v. Hatch, 527 F.3d 1010, 1015 

(10th Cir. 2018) (requiring “federal habeas courts to deny relief that is 

contingent upon a rule of law not clearly established”). 

For Mr. Montano’s statement to his wife, Mr. Chavez doesn’t 

identify a Supreme Court opinion clearly establishing the statement as 

testimonial. A statement is generally considered testimonial when the 

declarant makes a formal declaration in order to establish past events 

potentially bearing on a future prosecution. United States v. Morgan, 

748 F.3d 1024, 1038 (10th Cir. 2014). 

Even if we were to consider the arguments in Mr. Chavez’s 

supplemental habeas petition, he hasn’t cited any Supreme Court opinions 

suggesting that a codefendant’s statement to a spouse, prior to any contact 

from law enforcement, would be characterized as testimonial. So the state 

court’s consideration of this Confrontation Clause claim didn’t violate 

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clearly established Supreme Court precedent. And Mr. Chavez hasn’t 

shown a reasonably debatable argument to the contrary. 

Mr. Chavez also argues that introduction of Mr. Montano’s entire 

interrogation violates the Confrontation Clause. Mr. Chavez initially tried 

to use parts of Mr. Montano’s interrogation while challenging the 

admissibility of other parts. But the state court found that the defense had 

then withdrawn its challenge under the Confrontation Clause by offering 

the entire interrogation into evidence. Given that finding, the federal 

district court ruled that Mr. Chavez had not justified relief under the 

habeas standard. Mr. Chavez doesn’t present a colorable basis to question 

that ruling. 

2.2. Mr. Chavez doesn’t present a reasonably debatable habeas claim 

involving ineffective assistance of counsel. 

Mr. Chavez also claims that his counsel at trial and on appeal 

provided ineffective assistance in failing to raise the Confrontation Clause. 

For this claim, Mr. Chavez acknowledges that his trial counsel invoked the 

Confrontation Clause when challenging the admissibility of Mr. Montano’s 

statement to his wife. But Mr. Chavez claims that his 

 trial attorney should have raised the Confrontation Clause when 

objecting to the introduction of Mr. Montano’s interrogation 

and 

 appellate counsel should have raised the Confrontation Clause 

when appealing the conviction. 

The state court ruled that Mr. Chavez’s trial counsel had 

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 addressed the Confrontation Clause and 

 made reasonable strategic decisions regarding the use of 

Mr. Montano’s interrogation. 

The state court also ruled that Mr. Chavez’s appellate counsel had made a 

reasonable strategic decision to forgo challenging the admissibility of the 

entire interrogation. 

 For habeas relief, Mr. Chavez needed to show that the state court’s 

decisions had been contrary to, or an unreasonable application of, a 

Supreme Court opinion addressing ineffective assistance of counsel. 

28 U.S.C. § 2254(d)(1); see also Part 2.1, above. The state court applied 

the Supreme Court’s seminal opinion on ineffective assistance: Strickland 

v. Washington, 466 U.S. 668 (1984). There the Court had required a 

showing of both deficient legal representation and prejudice. Id. at 687–88, 

694. So Mr. Chavez had to show the state court’s application of Strickland

had been unreasonable. 

Mr. Chavez didn’t explain in the district court how the state court 

had unreasonably applied Strickland or another Supreme Court precedent. 

Mr. Chavez insists that he made this showing in his state-court filings. But 

the federal district court reasoned that Mr. Chavez hadn’t properly 

incorporated those documents. And Mr. Chavez provides no authority for 

his apparent assumption that the federal district court needed to excavate 

the voluminous state-court record to see where he had made this showing. 

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See Part 1, above. Absent any discussion of the relevant habeas standard, 

Mr. Chavez couldn’t have met his burden. See Part 1, above. So the federal 

district court’s rejection of his ineffective-assistance claims wasn’t 

reasonably debatable or wrong. 

3. Mr. Chavez doesn’t present a reasonably debatable habeas claim 

of a denial of due process from multiple trial errors or a related 

failure to provide effective assistance of counsel. 

In the habeas petition, Mr. Chavez also claimed a denial of due 

process from multiple trial errors. The district court rejected this claim, 

ruling that Mr. Chavez had not shown a failure of the state court to 

reasonably apply a Supreme Court opinion. Mr. Chavez hasn’t shown how 

a reasonable jurist could question the correctness of that ruling. 

Mr. Chavez also presents a related ineffective-assistance claim based 

on these trial errors. To prevail, Mr. Chavez would need to show that the 

state court’s rejection of this claim had been unreasonable or contrary to 

the Supreme Court’s test for ineffective assistance of counsel. See Parts 1 

& 2.2, above. But he hasn’t made a colorable showing under this standard. 

* * * 

We thus deny a certificate of appealability and dismiss the appeal. 

 Entered for the Court 

 Robert E. Bacharach 

 Circuit Judge 

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