State’s Mental-State Expert May Testify in Case-in-Chief; Trial Courts May Vary Order of Proof Under Rule 5-607(J)

I. Introduction

In State v. Cuellar (N.M. June 15, 2026) (unpublished; Rule 12-405 NMRA), the Supreme Court of New Mexico affirmed a first-degree murder conviction where the central dispute was not identity or actus reus—Defendant admitted killing his wife—but whether he possessed the deliberate intent required for willful and deliberate first-degree murder under NMSA 1978, Section 30-2-1(A)(1).

The appeal focused on a recurring trial-management question: whether the State may present expert testimony about a defendant’s capacity to form deliberate intent during the State’s case-in-chief, or whether such testimony is improper “anticipatory rebuttal” that becomes relevant only after the defense presents mental-health evidence. Defendant also argued that New Mexico’s criminal trial-order rule (Rule 5-607 NMRA) is mandatory in a way that forbids the State from presenting rebuttal-type evidence early.

II. Summary of the Opinion

The Court affirmed. It held:

  • The State’s expert testimony on whether psychiatric symptoms (including hallucinations and PTSD-related symptoms) necessarily preclude deliberate intent was relevant to the State’s burden to prove deliberate intent and therefore admissible in the State’s case-in-chief under Rules 11-401 and 11-402 NMRA.
  • Even if characterized as rebuttal evidence, New Mexico trial courts have long-standing discretion to vary the order of proof, and Rule 5-607(J) NMRA confirms that discretion.
  • The Court also explained that objections from the first (mistried) trial did not preserve the issue for appeal from the second trial; nevertheless, it addressed the merits in light of the direct appeal posture from a life-imprisonment case.

III. Analysis

A. Precedents Cited

1. Preservation and appellate review posture

  • State v. Allen, 2000-NMSC-002: Cited for the abuse-of-discretion standard for preserved evidentiary rulings and for the principle that appellate courts will not search the record to find preservation. The Court relied on Allen to reject the parties’ assumption of preservation where citations were limited to the first trial.
  • State v. Cordova, 1999-NMCA-117: A key procedural anchor—objections made in a first trial do not preserve the issue for appeal after a subsequent trial. The Court used Cordova to conclude that Defendant’s failure to renew the objection in the second trial meant the claim was unpreserved.
  • State v. Rojo, 1999-NMSC-001: Establishes that unpreserved evidentiary issues may be reviewed for plain error or fundamental error. The Court cited Rojo to frame the available review path once it concluded preservation was lacking.
  • State v. Gutierrez, 2003-NMCA-077: Noted for the appellate norm that courts do not typically perform uninvited error review when the appellant does not argue plain/fundamental error. The Court nonetheless proceeded given the direct-appeal context.
  • State v. Astorga, 2015-NMSC-007 and Campos v. Bravo, 2007-NMSC-021: Both establish the structure of plain/fundamental error review: first determine whether there was error, and only then assess whether it was plain/fundamental (including “grave doubts” about the verdict). The Court applied this framework but stopped at step one because it found no error.
  • Elane Photography, LLC v. Willock, 2013-NMSC-040: Used to decline review of an inadequately briefed point (the claim that the State’s expert attacked the defense expert’s methodology). The citation reinforces appellate briefing discipline: arguments must be supported by record citations.

2. Relevance vs. prematurity (timing of admissibility)

  • State v. Foster, 1998-NMCA-163: Distinguishes evidence that is prematurely admitted from evidence that is irrelevant. The Court used Foster to explain that even if the State’s expert was “early,” reversal is not warranted when the evidence would unquestionably have become admissible later in the trial.

3. Trial court discretion over order of proof

  • State v. Carabajal, 1920-NMSC-086: The foundational statement that trial circumstances often require flexibility and that the power to vary order of proof is vested in the trial judge. The Court invoked Carabajal to reject a rigid reading of criminal trial order.
  • State v. Cummings, 1957-NMSC-105: Reinforces that the order of trial and proof in a criminal case is “largely within the discretion of the court.” This case supports the Court’s conclusion that the discretion is entrenched and not displaced by modern procedural rules absent clear language.
  • State v. Mead, 1983-NMCA-055, rev’d sub nom. on other grounds by State v. Segotta, 1983-NMSC-092: Mead is cited for the breadth of discretion (“complete discretion to determine the order of proof”); Segotta is noted to clarify that the reversal was “on other grounds,” leaving the order-of-proof point intact for persuasive force.

B. Legal Reasoning

1. Why the expert testimony was relevant in the State’s case-in-chief

The Court treated deliberate intent as an element the State must prove beyond a reasonable doubt from the start. Under UJI 14-201 NMRA, the State must prove “[t]he killing was with the deliberate intention to take away the life of [the victim].” Because Defendant’s confession contained statements suggesting altered perception (e.g., that his wife “appeared to be a demon”), the jury could reasonably question whether he could deliberate.

The State’s expert testimony addressed that element directly: he interpreted Defendant’s police interactions as consistent with orientation to time and place, awareness of consequences, and planning capacity, and he referenced psychological literature indicating that hallucinations and PTSD symptoms do not necessarily preclude intent formation. Under Rule 11-401 NMRA, that testimony tended to make a consequential fact—capacity to deliberate—more probable; and under Rule 11-402 NMRA, relevant evidence is admissible unless another rule excludes it. The Court therefore rejected the premise that the testimony only became relevant once the defense “opened the door.”

2. The Court’s alternative holding: even if “rebuttal-like,” timing alone is not reversible error

The Court offered an important fallback: even assuming Defendant’s framing (that the testimony became relevant only after the defense presented incapacity evidence), the issue would be prematurity, not irrelevance. Citing State v. Foster, 1998-NMCA-163, the Court stated it will not reverse merely because evidence came in early when it would have been admissible later anyway.

This approach prevents “timing disputes” from becoming automatic reversal engines where the substantive admissibility is clear and the complained-of harm is essentially about sequencing.

3. Order of trial: Rule text and longstanding discretion

Defendant attempted a rule-based argument: because Rule 1-040(C)(3) NMRA (civil) states the order of proceedings applies “unless otherwise directed by the court,” while Rule 5-607 NMRA (criminal) states “[t]he order of trial shall be as follows” without parallel language, criminal courts purportedly lack authority to deviate.

The Court rejected that reading for two reasons:

  • Rule 5-607(J) NMRA expressly contemplates flexibility by allowing the court, for good cause, to permit either party to submit additional evidence “at any time before submission of the case to the jury.”
  • A century of New Mexico precedent—State v. Carabajal, 1920-NMSC-086 through State v. Cummings, 1957-NMSC-105 and State v. Mead, 1983-NMCA-055—recognizes that order of proof is largely discretionary in criminal trials.

The Court acknowledged that there may be situations where reordering proof could prejudice a defendant and constitute error, but concluded that this case did not present that scenario.

C. Impact

Although designated nonprecedential under Rule 12-405 NMRA, the decision consolidates several practically significant themes for New Mexico trial practice:

  • Element-first relevance in mental-state cases: Where the charged offense requires proof of deliberation, the State may proactively use expert testimony to address capacity to deliberate—even when the defense is expected to rely on mental-health evidence.
  • Reduced leverage of “anticipatory rebuttal” objections: The Court’s reasoning reframes many such objections as disputes about timing rather than admissibility; under Foster, prematurity alone is unlikely to justify reversal absent prejudice tied to the verdict’s reliability.
  • Reinforced trial-management discretion: The Court’s reliance on Rule 5-607(J) and longstanding cases strengthens the view that sequencing is generally a discretionary call, so long as it does not unfairly prejudice the defendant.
  • Preservation warning for retrials: The citation to State v. Cordova, 1999-NMCA-117 underscores that litigants must renew objections in a subsequent trial after mistrial; reliance on earlier objections is perilous.

IV. Complex Concepts Simplified

  • Case-in-chief vs. rebuttal: The case-in-chief is the main presentation of evidence to prove each element (State) or defenses (Defendant). Rebuttal responds to the opposing party’s evidence. Evidence is not “rebuttal” merely because it contradicts what the other side is expected to argue.
  • “Anticipatory rebuttal”: Evidence offered before the other side presents its case, aimed at undermining an expected defense. The Court effectively held that if the evidence helps prove an element the proponent already must prove, it is not improper simply because it also counters a likely defense.
  • Relevance (Rules 11-401/11-402): Evidence is relevant if it makes an important fact more or less likely. If it is relevant, it is generally admissible unless another rule excludes it.
  • Deliberate intent: For willful and deliberate first-degree murder, the State must prove a deliberate intention to kill—not merely a killing that occurred during anger or impulse. Evidence bearing on a defendant’s ability to plan, understand consequences, and make decisions can speak to this element.
  • Preservation: To complain on appeal, a party must usually object at the time of the alleged error in the trial that resulted in the conviction. Objections in a prior mistried proceeding generally do not carry over.
  • Plain error / fundamental error: Safety-valve doctrines allowing review of unpreserved claims. But courts first ask whether there was any error at all; without error, the analysis ends.

V. Conclusion

State v. Cuellar affirms that in a deliberate-intent homicide prosecution, the State may present expert testimony during its case-in-chief addressing whether a defendant’s reported psychiatric symptoms necessarily undermine the capacity to deliberate. The Court further reiterates that New Mexico trial courts possess broad discretion to manage the order of proof, supported both by Rule 5-607(J) NMRA and longstanding precedent, and it cautions that objections must be renewed after a mistrial to be preserved for appeal.