“Let the Doctors Speak” – State v. Soto and the New Mandate Against Undue Restriction of Expert Medical Testimony in Child-Abuse Homicide Trials

1. Introduction

Court & Date: New Mexico Supreme Court, 3 June 2025 (State v. Soto, No. S-1-SC-39785).

Parties: State of New Mexico (Appellee) v. Ricardo Soto (Appellant).

Background: Two–year-old Jeremiah Nevarez died from catastrophic brain swelling. The State alleged that his father, Ricardo Soto, intentionally abused him, causing fatal blunt-force injuries. The defence maintained the injuries arose from an earlier accident and a subsequent “slow re-bleed.” After a trial dominated by competing medical experts, a jury convicted Soto of intentional child abuse resulting in death, a capital felony. On appeal Soto challenged:

Sufficiency of the evidence – contending expert testimony was speculative under State v. Consaul.
Character-evidence ruling – objecting to a pre-trial order allowing the State to rebut “good parent” evidence with Soto’s unrelated perjury conviction.
Admission of statistical evidence – arguing that population-based fall statistics usurped the jury’s function.

2. Summary of the Judgment

The Supreme Court (Justice Zamora) unanimously affirmed. Key holdings:

Sufficiency: Combining robust expert testimony (identifying two acute skull fractures caused by “high-energy” trauma) with circumstantial evidence (exclusive custody, delayed 911 call, flight to Mexico), the record easily supported intent and causation. Consaul distinguished.
Expert-testimony guidance: Trial courts should not compel physicians to couch opinions only in “consistent with” language; experts must be allowed to express the full differential diagnosis and certainty warranted by the data.
Character evidence: Admitting the perjury conviction would have been error under Rule 11-404(A)(2) (irrelevant trait), but it could fit Rule 11-404(B)(2) (consciousness of guilt). Any error was harmless because the conviction was never actually introduced and the evidentiary landscape was overwhelming.
Statistical evidence: Population statistics on injury causation are admissible when properly grounded and used to help the jury evaluate medical opinions; they did not improperly bolster credibility or shift the burden of proof.

3. Analysis

3.1 Precedents Cited

State v. Consaul (2014): Vacated a suffocation-based child-abuse conviction due to equivocal medical proof. Soto distinguishes it by emphasising (i) more conclusive injuries (visible bilateral skull fractures) and (ii) stronger corroborative circumstantial evidence.
State v. Cunningham (2000) & Sena (2008): Standard “view evidence in the light most favourable to the verdict.”
Wilson (2001), Sheldon (1990), Pennington (1993): Prior child-abuse cases allowing exclusive-custody and timing evidence to establish opportunity.
Alberico (1993) & Duran (1994): Bedrock New Mexico authority on expert-opinion admissibility and de-emphasis of judicial gate-keeping where experts are properly qualified.
Trujillo (1981) & Telles (2019): Flight or delay in seeking help as circumstantial proof of consciousness of guilt.
People v. Julian (Cal. 2019): Relied upon by Soto to attack statistics; court distinguishes it as limited to credibility-bolstering context.

3.2 Court’s Legal Reasoning

Sufficiency Framework
The Court reminds that appellate review is deferential; juries resolve expert battles. It methodically catalogues the State’s five experts, two skull fractures, rapid swelling, and high-energy explanation, all anchored to a narrow temporal window when Soto alone had care. Add motives (avoidance of paternity, sporadic visits) and consciousness of guilt (flight) – a rational juror could convict.
Distinguishing Consaul
– Consaul involved hypoxic injury with no external signs; here, objective fractures on imaging.
– Experts there voiced only “concerns” or “possibility”; here they reached “only reasonable explanation” and “reasonable medical certainty.”
– Supporting non-medical proof was scant in Consaul; plentiful in Soto.
“Let the Doctors Speak” – Evidentiary Guidance
The Court criticises defence-driven motion practice that hemmed witnesses into “consistent with” language, then invoked that vagueness on appeal as insufficiency. Trial courts should not allow such artificial constraints; qualified experts may detail differential diagnosis and causation opinions. Shielding the jury from legitimate expert certainty “vitiates the most basic function of a jury.” (¶ 30).
Character-Evidence Misstep but Harmless
– Rule 11-404(A)(2): if defendant shows good parenting, State may rebut only with parenting-related traits.
– Perjury conviction is irrelevant to parenting → trial court’s pre-trial ruling erroneous if based on 404(A).
– Yet same evidence could come in under 404(B)(2) to show consciousness of guilt, and never actually came in; plus the jury heard favourable parenting anecdotes anyway. Thus no prejudice.
Statistical Evidence
The Court treats injury-probability data like any other expert tool: admissible if helpful and non-misleading. Neither statistic suggested Jeremiah’s individual probability of abuse; they illustrated medical consensus that fatal skull fractures from a low fall are exceedingly rare. Proper cross-examination, not exclusion, is the remedy.

3.3 Likely Impact of the Decision

Expert Testimony in Abuse Cases: Trial judges must allow full-strength causation opinions where the science supports them. Expect fewer defence victories based on artificially muted expert language.
Sufficiency Appeals: Soto narrows Consaul to its facts; prosecutors can rely primarily on medical opinion if (a) injuries are objectively verifiable, and (b) corroborative circumstances exist.
Rule 404 Landscape: Clarifies that rebuttal must match the trait opened by the defence, but the same evidence might still enter under 404(B) if tied to consciousness of guilt.
Statistics in Court: Endorses medical-probability statistics so long as they are not used to vouch for witness credibility or quantify guilt. This will influence personal-injury, medical-malpractice, and other scientific-evidence contexts.

4. Complex Concepts Simplified

Differential Diagnosis – A step-by-step method doctors use to rule out possible causes until the most plausible one remains; the Court says jurors should hear that full process.
Consciousness of Guilt – Behaviour (flight, lying, tampering) after the event that suggests the person knows they committed a crime.
Rule 11-404(A) vs 11-404(B) – 404(A) deals with using character to prove conduct (and its limited rebuttal); 404(B) allows other-acts evidence for non-character purposes (motive, intent, plan, consciousness of guilt, etc.).
Harmless Error – Even if the trial judge made a mistake, an appellate court won’t reverse unless there’s a reasonable probability it affected the verdict.
Sufficiency Review – On appeal, the court asks whether any reasonable juror could convict, viewing evidence in the State’s favour; it does not re-weigh credibility.
Statistical Evidence – Data describing how often an event happens in the general population; admissible if it helps the jury and is not unduly confusing.

5. Conclusion

State v. Soto reinforces New Mexico’s willingness to sustain child-abuse homicide convictions anchored in modern medical science. The Court simultaneously:

Clarifies that expert physicians may deliver forthright causation opinions without artificial linguistic shackles;
Tethers Consaul to fact-patterns with ambiguous medical evidence;
Refines the interplay between character rebuttal and consciousness-of-guilt evidence under Rule 404;
Affirms that properly-grounded statistics are fair game in elucidating medical testimony.

The net effect is to empower fact-finders with the full explanatory power of scientific evidence while guarding against its misuse. Trial courts should heed the Court’s admonition: when experts speak within their competence, “excluding such evidence vitiates the most basic function of a jury.”