Confrontation, DNA Evidence, and Prior Bad Acts: A Closer Look at Commonwealth v. Nascimento-Depina, SJC-13664 (2025)
On May 8, 2025, the Massachusetts Supreme Judicial Court (SJC) issued its decision in Commonwealth v. Antonio Nascimento-Depina, a troubling and legally significant case involving the aggravated rape and indecent assault of a child. The decision affirms the convictions but provides critical clarification on two recurring evidentiary issues in criminal trials: (1) the constitutional limits of expert testimony under the confrontation clause, especially when a testifying analyst substitutes for a non-testifying one; and (2) the proper admission of prior bad acts to show the nature of the relationship between the defendant and the victim.
At the heart of the case is a brutal and tragic crime: the repeated sexual abuse of a 12-year-old girl by her maternal grandfather. But beyond the gut-wrenching facts lies a dense web of evidentiary rulings with consequences for how trial courts must handle DNA evidence and prior misconduct—issues that frequently surface in sexual assault prosecutions.
Case Background
Antonio Nascimento-Depina was indicted in 2018 for sexually abusing his twelve-year-old granddaughter while they were living in Taunton. At trial in Bristol County Superior Court, the Commonwealth presented the testimony of the victim and introduced DNA evidence allegedly corroborating her account. The victim described multiple forms of sexual penetration and provided graphic, detailed recollections of the assault.
One key element of the Commonwealth’s case was the DNA evidence obtained from the defendant’s bedding, which the victim said had been stained with semen after the assault. A sample taken from the bedding yielded a male DNA profile that matched the defendant. However, critically, the DNA of the victim was not detected on any of the tested samples. This gap in the scientific evidence would become the cornerstone of the defense strategy.
Procedural Posture and Issues on Appeal
The defendant was convicted by a jury of two counts of aggravated rape of a child and three counts of indecent assault and battery on a child under fourteen. On direct appeal, he raised two main arguments:
That his confrontation rights under the Sixth Amendment and Article 12 of the Massachusetts Declaration of Rights were violated when the Commonwealth’s expert, Jessica Hart, testified to conclusions drawn by another, non-testifying DNA analyst (Kira Snyder).
That the trial judge abused his discretion by admitting prior bad act evidence that the defendant had inappropriately touched the victim on a previous occasion, when the family lived in Chelsea.
The SJC transferred the case from the Appeals Court on its own initiative, signaling that the issues raised—especially the confrontation question—had broader implications for Massachusetts jurisprudence.
I. The Confrontation Clause and DNA Analysts
A. The Testimony at Issue
The confrontation issue arose from the testimony of Jessica Hart, a technical reviewer at the Massachusetts State Police Crime Lab. Hart did not perform the DNA testing herself. That work had been done by Snyder, who authored the report. By the time of trial, Snyder was unavailable, and Hart was substituted as a witness. Hart testified in detail about Snyder’s findings: the semen on the bedding matched the defendant’s DNA and excluded the victim as a source. The defense did not object to Hart’s substitution, and in fact, defense counsel ultimately requested that Snyder’s report be admitted into evidence during cross-examination.
B. The Legal Framework
The SJC acknowledged that Hart’s testimony, insofar as it relayed the findings of a non-testifying analyst, violated established confrontation principles under Melendez-Diaz v. Massachusetts, Bullcoming v. New Mexico, and its own prior decision in Commonwealth v. Greineder. Under this body of law, a defendant has the right to cross-examine the analyst who actually performed the forensic testing, particularly when the results are testimonial in nature.
Expert witnesses may rely on data produced by others, but cannot introduce testimonial hearsay from non-testifying experts during direct examination. Here, Hart’s testimony went beyond explaining her review of Snyder’s work; she effectively stood in as a surrogate expert, relaying Snyder’s substantive conclusions without providing her own independent opinion. This ran afoul of the confrontation clause.
C. Waiver and Standard of Review
Because the defense did not object to Hart’s testimony and in fact pursued the introduction of Snyder’s report as part of its own trial strategy, the SJC reviewed the error under the “substantial risk of a miscarriage of justice” standard. The court found no such risk, citing multiple factors:
The defense embraced the DNA evidence as exculpatory. Defense counsel argued that the absence of the victim’s DNA supported the theory that she had fabricated the allegations after witnessing a sexual act between the defendant and another woman.
The DNA evidence did not wholly corroborate the victim’s account, which enhanced the defense's credibility rather than undercut it.
The Commonwealth’s case ultimately hinged on the jury’s assessment of the victim’s credibility, which remained consistent and specific from the time of disclosure through trial.
In short, the SJC found that although a confrontation error occurred, it did not undermine the fairness of the trial in light of the entire record.
II. Prior Bad Acts: When Is Evidence of Earlier Misconduct Admissible?
The second issue on appeal concerned the trial judge’s decision to allow the victim to testify that the defendant had previously touched her inappropriately while they were living in Chelsea, before the family moved to Taunton. This earlier conduct included touching the victim’s breasts and buttocks.
A. Governing Law
Massachusetts law generally prohibits the introduction of prior bad acts to show criminal propensity. See Mass. G. Evid. § 404(b). But such evidence may be admitted for limited, non-propensity purposes, such as showing:
A pattern of behavior
Motive or intent
The nature of the relationship between the victim and the defendant
In sexual assault cases involving children, courts have consistently held that limited testimony about earlier sexualized conduct may be admitted to help the jury understand the context of the alleged abuse and the nature of the relationship. See Commonwealth v. Dwyer, 448 Mass. 122 (2006).
B. The Court’s Rationale
The SJC concluded that the trial judge did not abuse his discretion in admitting the prior misconduct evidence. Several factors supported the ruling:
The prior acts involved the same victim and occurred in the same domestic setting (the family home).
The earlier abuse was relatively close in time to the charged offenses.
The prosecutor’s inquiry into the prior acts was brief and limited in scope.
The testimony helped establish the dynamic of control and grooming between the grandfather and his granddaughter, which informed the jury’s understanding of the charged offenses.
The Court also rejected the defense’s argument that the judge erred by failing to give a sua sponte limiting instruction. No such instruction was requested, and the court reaffirmed that Massachusetts trial judges are not obligated to provide one absent a request. The SJC declined to adopt a new rule requiring automatic limiting instructions for uncharged misconduct.
Key Takeaways
1. Surrogate Expert Testimony Remains a Minefield
The SJC’s reaffirmation of Greineder and Chappell underscores that prosecutors must tread carefully when presenting scientific evidence through technical reviewers. Even where the substitution seems logical—such as when a supervisor reviews and approves the underlying report—it can raise confrontation concerns if the testifying witness merely acts as a mouthpiece for the absent analyst.
This case also serves as a reminder to defense counsel: strategic decisions at trial, such as failing to object to a surrogate analyst or using hearsay evidence to one’s advantage, can limit appellate options. Here, defense counsel leaned into the DNA findings because they were favorable. That tactical choice effectively neutralized the confrontation argument on appeal.
2. Prior Misconduct Evidence Requires Careful Calibration
The SJC reaffirmed that evidence of prior inappropriate touching can be admissible in child sex abuse cases when it sheds light on the relationship between the accused and the victim. The key is proportionality: the evidence must be limited in scope, temporally and factually relevant, and not so inflammatory that it unfairly sways the jury.
Trial counsel should always consider requesting a limiting instruction, especially when the line between character evidence and contextual evidence becomes blurry. Although the SJC declined to impose a sua sponte rule in this case, it left open the possibility that in a closer case, failure to instruct the jury might be reversible.
3. Victim Credibility Remains Central
The SJC's opinion repeatedly emphasized that the trial turned on the jury's evaluation of the victim’s testimony. Despite the confrontation error and the absence of the victim’s DNA on the bedding, the victim’s consistent, age-appropriate account—with details stretching from the day of the assault to trial—carried the case for the Commonwealth. The decision implicitly affirms that in many sexual assault prosecutions, especially those involving children, the credibility and demeanor of the complainant are often dispositive.
Final Thoughts
Commonwealth v. Nascimento-Depina presents a complex and emotionally fraught fact pattern, but its legal significance goes beyond the horrific abuse at its core. It clarifies how Massachusetts courts should handle surrogate expert testimony in light of confrontation rights and reaffirms the boundaries for admitting prior bad acts in sexual assault prosecutions.
For prosecutors, the case is a cautionary tale about relying too heavily on testimony that walks too close to the hearsay line. For defense lawyers, it highlights the strategic calculations that can shape confrontation claims—sometimes cutting both ways. And for trial judges, it offers a steadying guide to balancing probative value and prejudice when prior misconduct evidence is introduced.
Above all, the case underscores that even in high-stakes, emotionally difficult trials, procedural rigor matters. The reliability of our verdicts—and the legitimacy of our criminal justice system—depends on it.