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Commonwealth v. Shu Feng Hsu

2026-09-09

Authorities cited

Opinion

majority opinion

NOTICE: All slip opinions and orders are subject to formal revision and are superseded by the advance sheets and bound volumes of the Official Reports. If you find a typographical error or other formal error, please notify the Reporter of Decisions, Supreme Judicial Court, John Adams Courthouse, 1 Pemberton Square, Suite 2500, Boston, MA, 02108-1750; (617) 557-1030; [email protected]

SJC-13855

COMMONWEALTH vs. SHU FENG HSU.

Norfolk. April 6, 2026. - September 9, 2026.

Present: Budd, C.J., Gaziano, Kafker, Wendlandt, Georges,

Dewar, & Wolohojian, JJ.

Homicide. Evidence, Expert opinion, Relevancy and materiality.

Witness, Expert. Child Abuse. Jury and Jurors. Practice,

Criminal, Jury and jurors.

Indictment found and returned in the Superior Court Department on January 11, 2019.

The case was tried before Douglas H. Wilkins, J.

The Supreme Judicial Court on its own initiative

transferred the case from the Appeals Court.

Christopher DeMayo (Debra D. DeWitt also present) for the defendant.

Meagen K. Monahan, Assistant District Attorney, for the Commonwealth.

The following submitted briefs for amici curiae:

V. Marika Meis, of New York, Radha Natarajan, Nina Thacker, David R. Rangaviz, Sharon L. Beckman, Lisa M. Kavanaugh, & Katharine Naples-Mitchell for New England Innocence Project & others.

Thomas J. Carey, Jr., & Mark S. Brodin for Mark S. Brodin.

Mark Loevy-Reyes for Center for Integrity in Forensic Sciences & others.

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GAZIANO, J. The defendant, Shu Feng Hsu, was charged with

murder in the first degree for the death of her eleven month old

niece, Chloe Chen. Before trial, the defendant filed motions in

limine to exclude expert testimony regarding abusive head trauma

-- a medical diagnosis describing injuries to the skull or brain

of a young child due to inflicted blunt impact or violent

shaking -- and requesting a hearing pursuant to Daubert v.

Merrell Dow Pharms., Inc., 509 U.S. 579, 585-595 (1993), and

Commonwealth v. Lanigan, 419 Mass. 15, 24-26 (1994). Following

a Daubert-Lanigan hearing, the trial judge allowed the motions

in part and denied them in part, ruling that expert witnesses

could testify that the victim showed symptoms "consistent with"

abusive head trauma but could not testify that abusive head

trauma "was the cause" of the victim's death. The judge also

prohibited expert testimony that "short falls cannot cause

[abusive head trauma]," among other restrictions.

A Norfolk County jury convicted the defendant of the lesser

included offense of involuntary manslaughter under the theories

of battery and wanton or reckless conduct. The defendant

appealed, arguing that the evidence was insufficient to support

the conviction and that the judge abused his discretion by

allowing the admission of expert testimony regarding abusive

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head trauma and short falls. We transferred the appeal to this

court on our own motion and now affirm.1

Background. 1. Facts. Because the defendant challenges

the sufficiency of the evidence, we summarize the evidence

presented at trial in the light most favorable to the

Commonwealth. See Commonwealth v. Latimore, 378 Mass. 671, 676-677 (1979).

a. The victim's death. In February 2018, the victim, an

eleven month old girl, lived on the second floor of a home in

Quincy with her parents and grandparents. The defendant and her

husband, the victim's uncle, lived on the first floor of the

home with their two year old daughter. The victim was generally

a healthy child with no major illnesses. Several days per week,

while the other adults in the household were at work outside the

home, the defendant would watch her daughter and the victim.

On the morning of February 15, 2018, the victim's

grandmother and father cared for the victim. The grandmother

watched the victim from 8 A.M. until she left for work between

9:30 and 10 A.M. The victim's father then watched her until

1 We acknowledge the amicus briefs submitted in support of the defendant by the New England Innocence Project, the Massachusetts Association of Criminal Defense Lawyers, the Boston College Innocence Program, the Committee for Public Counsel Services, the Criminal Justice Institute at Harvard Law School, and the Innocence Project; Mark S. Brodin; and the Center for Integrity in Forensic Sciences, Cyrille Rossant, Waney Squier, Jane Turner, Steven Gabaeff, and Judy Melinek.

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around 2 or 2:30 P.M., when he left the house to go to work and

the defendant took over as the victim's caregiver in the firstfloor apartment. Neither the grandmother nor the father

observed any medical issues with the victim. Video recordings

from surveillance cameras installed in the home, which were

admitted in evidence at trial, show a healthy and active infant.

She ate and watched television alongside the defendant in the

living room, cruised in her walker, babbled, reached for

objects, fed herself, and cried sporadically. Eventually, the

defendant took her daughter and the victim to the defendant's

bedroom for a nap.

At around 4:20 P.M., approximately two and one-half hours

after the defendant and the children went into the defendant's

bedroom, a surveillance camera in the living room captured the

sound of a baby intermittently crying for about five minutes.

At around 4:25 P.M., the camera recorded the sound of eleven

thuds occurring over the span of approximately one minute. The

eleven thuds are interspersed with the sound of the baby crying.

After the eleventh thud, the crying slowly stops and is replaced

by coughing and gagging sounds.

At 4:29 P.M., the defendant called 911. She told the 911

operator that the victim seemed "soft" and was having difficulty

breathing. A Quincy police officer arrived at the home

approximately six minutes later. He noticed the victim's

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breathing was shallow and that she appeared to be seizing. The

officer did not recall if he observed a mark or a bruise on the

victim's head.

Paramedics arrived in an ambulance shortly thereafter. As

the victim was placed in the ambulance, one paramedic noticed

that the victim had a small bruise or abrasion on her forehead,

and that she did not have a fever. The defendant told the

paramedic that the victim had slept longer than usual that day

and that she suffered multiple seizures in the moments before

the defendant called 911.

The victim was taken to Boston Medical Center. Upon the

victim's arrival at the hospital, Dr. James Holsapple, the

neurosurgeon who performed surgery on the victim, observed that

she was unconscious and seizing and that her pupils were

nonreactive. Holsapple did not observe a bruise on the victim's

forehead or other conspicuous signs of trauma on her arrival.

However, contemporaneous medical records indicate that the

victim presented with a bruise on her forehead that may not have

been recent. A computed tomography (CT) scan showed that the

victim had an acute subdural hematoma2 covering most of the

2 A subdural hematoma is an accumulation of blood in the space between the brain and the dura. See Commonwealth v. Millien, 474 Mass. 417, 421 (2016). The dura is the membrane between the skull and the brain. Id. at 421 n.4. Holsapple explained that "acute" indicates that the blood has "just come

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surface of the left hemisphere of her brain; the victim's brain

had an eight millimeter midline shift, which meant that the

middle of her brain was pushed over from its normal position by

eight millimeters; and the left side of her brain was swollen.

Based on the victim's critical injuries, Holsapple

performed brain surgery approximately one hour and fifteen

minutes after her arrival at the hospital. He found a large

volume of high pressure, acute blood beneath the victim's skull.

Holsapple was able to remove the subdural hematoma, but once it

was removed, the victim became unstable, prompting emergency

resuscitation efforts that caused additional brain swelling.

The victim was subsequently transferred to the pediatric

intensive care unit. She died on February 17, 2018.

b. Investigation and arrest. On February 16, 2018, the

day after the victim was taken to the hospital, the defendant

participated in an interview with police. The defendant said

that the victim cried a lot and had done so the previous day,

but she denied that the crying frustrated her. The defendant

told the interviewing officers that she had called 911 because

the victim, who had been sleeping, suddenly clenched in a way

that suggested she may be suffering from a seizure. The

out," and that subdural hematomas can occur in the absence of conspicuous scalp trauma or bruising.

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defendant denied touching, dropping, or shaking the victim,

noting that if someone had struck her, there would have been a

bruise or blood. The same day as the interview, police removed

and seized memory cards from the surveillance cameras inside and

around the defendant's home.3

The police arrested the defendant at her home on November

20, 2018, where, after searching for twenty minutes, they found

her hiding in a bedroom closet.

c. Commonwealth's expert witnesses. Dr. Anand Shah and

Dr. Christina Stanley, medical examiners in the office of the

chief medical examiner, performed the victim's autopsy. The

autopsy revealed multiple injuries not attributable to medical

intervention, including bruises on the victim's head, left

forearm, and torso. Also discovered were multiple brain and

3 Although there was a surveillance camera in the

defendant's bedroom, there was no memory card in the camera, so there are no video recordings available from that room. During the police interview, the defendant stated that she sold the memory card from the bedroom camera before February 15, 2018, although she could not remember to whom she sold it.

When the police went to the defendant's home, the living room camera's memory card was hidden inside a "little egg." The defendant told the police that she had removed the memory card from the living room camera at her husband's request and set it on the table, and that her two year old daughter grabbed the memory card from the table and hid it in the egg.

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retinal hemorrhages, and evidence of one brain hemorrhage that

appeared to be weeks or months old.4

At trial, Shah directed the jury's attention to details in

certain autopsy photographs. While showing the jury a

photograph of the left side of the victim's face, Shah pointed

to "areas of kind of red to blue, to purple bruising." He next

showed a photograph of her outer left forearm and highlighted

bruising that was "blue-purple in coloration and linear," and

that there "look[ed] to be about three bruises." The next

photograph showed "injuries of the left side of the [victim's]

face" that Shah attributed to blunt force trauma, not medical

intervention. Another photograph of the victim's face showed

"bruising of [the] left cheek area" as well as "bruising around

the left eyebrow" and "some bruising near the bottom of the left

ear." Photographs of the right side of the victim's head showed

"bruising of the right forehead" that had a "blue-purple

discoloration."5 Shah testified that the victim's death was a

4 Holsapple had not found evidence of an old subdural hematoma during surgery.

5 On cross-examination, Shah acknowledged that a death notification report transmitted from Boston Medical Center indicated "no outward signs of trauma"; bruising to the victim's left ear may have been attributable to manipulation of the ear during surgery; and the victim developed a significant coagulopathy, which increased the probability of bruising due to medical intervention, especially where the victim was subject to ninety minutes of chest compressions. These concessions in Shah's testimony do not undermine our determination that the

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result of multiple significant blunt force impacts to the head

that had been recently inflicted. Shah noted that the victim's

blunt force injuries were not consistent with her bumping her

head on a crib or a short fall of less than three feet.

Similarly, Stanley, a neuropathologist, opined that the

victim's subdural hematoma was the result of significant trauma.

She testified that the subdural hematoma was inconsistent with a

rebleed of the older hemorrhage, because the older hemorrhage

was too thin to have caused the volume of bleeding that

occurred.

Dr. Kimberly Schwartz, a child abuse pediatrician and

member of the Boston Medical Center child protection team, also

testified at trial for the Commonwealth. Schwartz explained

that abusive head trauma involves "injury to the brain or around

the brain of a young child that is . . . not accidental."

Schwartz reviewed the victim's medical records, spoke with the

victim's parents and her medical team, and conducted a visual

examination of the victim before completing a differential

diagnosis6 of the victim's injuries. Schwartz concluded that the

evidence was sufficient when viewed in the light most favorable to the Commonwealth. See Latimore, 378 Mass. at 676-677.

6 A differential diagnosis "is a standard scientific technique of identifying the cause of a medical problem by eliminating the likely causes until the most probable one is isolated" (citation omitted). Hick's Case, 62 Mass. App. Ct. 755, 761 (2005).

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victim's injuries were "consistent with abusive head trauma."

She also opined that the victim's subdural hematoma was

inflicted "[s]hortly before [the victim] presented to the

hospital" and that the level of force necessary to inflict a

subdural hematoma is force "not from . . . normal infant care."

d. Defendant's expert witnesses. The defendant presented

two expert witnesses. First, Dr. Janice Ophoven, a pediatric

forensic pathologist, shared her expert opinion after reviewing

the victim's case file, police and medical records, and autopsy

reports. Ophoven testified that there was evidence the victim

had sustained a prior head injury weeks or months before

February 15, 2018, and opined that the victim "suffered a

traumatic brain injury due to blunt-force trauma associated with

chronic and acute subdural bleeding." She explained that

"chronic" "means that it's been going on for a significant

period of time," and noted that children with chronic subdural

fluid can suffer an immediate collapse from falling and "banging

their head on the crib or on the floor." Ophoven further

testified that the victim went into cardiac arrest when doctors

made the incision releasing the pressure in her brain, and that

the significant amount of blood documented during the autopsy

was due to surgical intervention rather than blunt force impact

to the victim's head.

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Dr. John Galaznik, a pediatrician, similarly testified that

the victim's injuries indicated preexisting subdural bleeding

alongside some new bleeding, and that acute blood on a CT scan

is not necessarily from the same day, but rather can be one to

ten days old. He then opined that the victim's injuries could

have been the result of rebleeding of a prior injury after a

"trivial" impact or bump to the head, and that the bump could

have occurred one to seven days before the victim was taken to

the hospital.

2. Procedural history. On January 11, 2019, a grand jury

indicted the defendant on a charge of murder in the first degree

in violation of G. L. c. 265, § 1. In February 2023, the

defendant filed two motions in limine to exclude expert

testimony regarding abusive head trauma. After an evidentiary

Daubert-Lanigan hearing, on March 6, 2023, the defendant's

motions in limine were allowed in part and denied in part.

A fourteen-day jury trial commenced the following day. At

the close of the Commonwealth's case, the defendant moved for a

required finding of not guilty, which the judge allowed with

respect to murder in the first degree on a theory of deliberate

premeditation but otherwise denied. The defendant then renewed

her motion for a required finding of not guilty at the close of

all evidence, which the judge also denied. The jury found the

defendant guilty of involuntary manslaughter on theories of

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battery and wanton or reckless conduct. The defendant filed a

motion for a required finding of not guilty after the discharge

of the jury, which was denied. The judge sentenced the

defendant to a term of from five to seven years in State prison.

The defendant appealed, and we transferred the appeal to

this court on our own motion.

Discussion. On appeal, the defendant argues that (1) the

evidence was insufficient to convict her of involuntary

manslaughter, and (2) the trial judge abused his discretion in

permitting expert testimony that the victim's injuries were

"consistent with" abusive head trauma and that the victim's

injuries were not consistent with a short fall. We begin with

the sufficiency of the evidence.

1. Sufficiency of the evidence. In reviewing a

sufficiency claim, we "determine whether, viewing the evidence

in the light most favorable to the Commonwealth, any rational

finder of fact could have found each of the elements of the

offense beyond a reasonable doubt." Commonwealth v. Jones, 477

Mass. 307, 316 (2017), citing Latimore, 378 Mass. at 676-677.

"A conviction may rest exclusively on circumstantial evidence,"

Jones, supra, and the inferences drawn by the jury from the

evidence "need only be reasonable and possible and need not be

necessary or inescapable" (citation omitted), Commonwealth v.

Kelly, 470 Mass. 682, 693 (2015). "If, from the evidence,

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conflicting inferences are possible, it is for the jury to

determine where the truth lies, for the weight and credibility

of the evidence is wholly within their province" (citation

omitted). Id.

"Involuntary manslaughter is an unlawful homicide (1) where

wanton [or] reckless conduct causes death, or (2) where an

unintentional killing result[s] from a battery not amounting to

a felony which the defendant knew or should have known

endangered human life" (quotation and citation omitted).

Commonwealth v. Simpson, 434 Mass. 570, 590 (2001). Wanton or

reckless conduct is "intentional conduct that create[s] a high

degree of likelihood that substantial harm will result to

another person" (citation omitted). Commonwealth v. O'Brien,

494 Mass. 288, 297 (2024). The crime of assault and battery

requires "the intentional and unjustified use of force upon the

person of another, however slight" (citation omitted).

Commonwealth v. Sheppard, 404 Mass. 774, 776 (1989).

At trial, the jury were presented evidence that the victim

was a healthy eleven month old on the morning of February 15,

2018. The victim's family members testified that the victim was

behaving normally before she was left in the defendant's care,

and video recordings from inside the home show the victim

eating, interacting with family members, and cruising in her

walker. The Commonwealth also presented evidence that the

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defendant was the victim's sole caretaker in the hours

immediately before the 911 call. See Collazo v. Commonwealth,

483 Mass. 1025, 1027 (2020) (evidence warranted finding that

defendant inflicted injuries on infant victim where jury could

have found defendant was child's sole caretaker during key time

period); Commonwealth v. Azar, 32 Mass. App. Ct. 290, 305

(1992), S.C., 435 Mass. 675 (2002), and 444 Mass. 72 (2005)

(considering fact that defendant was child's sole caretaker

before child's death in assessing sufficiency of evidence for

conviction of murder in second degree).

A video recording of the victim's home on the afternoon of

February 15, 2018, which was played for the jury, captured the

sound of a baby crying, followed by eleven distinct thuds, and

then the defendant speaking on the telephone with the 911

operator. A paramedic who responded to the 911 call testified

that, upon arriving at the home, the victim was unresponsive

with her eyes rolled back, and that she had a visible bruise on

her head.7 Given the difference in the victim's health before

7 Even where there was some inconsistency between witnesses whether bruising appeared on the victim's head before her arrival at the hospital, the jury were entitled to credit testimony indicating its presence. See Commonwealth v. Miranda, 458 Mass. 100, 113 (2010), cert. denied, 565 U.S. 1013 (2011), S.C., 474 Mass. 1008 (2016) ("To the extent that conflicting inferences may be drawn from the evidence, it is for the jury to decide which version to credit"). That is especially true here, where the jury reviewed autopsy photographs of the victim and Shah, the medical examiner, opined that bruising on the victim's

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and after the sound of the eleven thuds, and the repetitive

nature of the noises (interspersed with the baby's cries and

culminating in coughing and gagging sounds), the evidence

supported a reasonable inference that the defendant injured the

victim. See Commonwealth v. Lacrosse, 494 Mass. 475, 503 (2024)

("the jury were required to ultimately decide what the

surveillance video footage showed"); Commonwealth v. Forte, 469

Mass. 469, 482 n.23 (2014) ("Interpretation of the footage in

relation to the witnesses' testimony was for the jury").

The jury heard expert testimony further supporting the

reasonable inference that the victim's injuries were caused by

recent, nonaccidental blunt force impact. Describing his

observations from the autopsy, Shah opined to a reasonable

degree of medical certainty that the victim died from blunt

force head injuries caused by significant, repeated impact.

While the jury reviewed autopsy photographs of the victim, Shah

pointed to bruising on the left side of the victim's head and a

bruise on the right side of her forehead. The jury "were well

able to make their own evaluation of the mark[s] shown in the

head was not consistent with medical intervention. Moreover, regardless of whether the jury credited testimony on the existence of bruising before the victim received medical intervention, the jury could have credited Schwartz's testimony that abusive head trauma often manifests without external symptoms.

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photograph[s]." Commonwealth v. Kelly, 57 Mass. App. Ct. 201,

213 (2003). Shah also indicated that the victim's injuries were

new, not old, and that they were not consistent with bumping her

head on a crib or a short fall of less than three feet. Cf.

Collazo, 483 Mass. at 1026 (among expert testimony establishing

infant victim died due to injuries inflicted on him, medical

examiner testified to autopsy finding of blood clot on victim's

brain "that was not old enough to have formed a membrane").

Similarly, Stanley testified to a reasonable degree of

medical certainty that the victim's subdural hematoma was caused

by "significant trauma, shearing-type trauma." She explained

that this trauma caused multiple veins between the victim's

brain and dura to tear. When asked whether the victim's

subdural hematoma could have resulted from a rebleed of an older

hematoma, she stated that "it wasn't caused by that" and

explained that "the . . . older hemorrhage . . . [was] just too

thin to have a vessel in it that's big enough to cause that

volume of bleeding."

Schwartz testified that the victim's injuries were

"consistent with abusive head trauma" to a reasonable degree of

professional certainty. As to the victim's subdural hematoma,

she opined that it was not consistent with a rebleed, and

explained that the force necessary to inflict a subdural

hematoma is generally force beyond that used in normal child

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care. And when asked whether the victim's subdural hematoma was

consistent with a short fall from a sitting position, Schwartz

answered, "No, I did not believe so" and that a subdural

hematoma from a short fall "is not the same kind of size of

subdural that we see in this case."

The defendant's experts disagreed on a number of points.

As previously noted, Ophoven testified that the victim suffered

from chronic subdural bleeding and noted that a child with

chronic subdural fluid could collapse from falling and bumping

his or her head. She attributed the amount of blood found

during the autopsy to surgical intervention rather than blunt

force impact.

Galaznik opined that the victim's injuries were caused by

rebleeding of an older injury activated by a bump to the

victim's head. He explained that this bleeding could have

started days before the victim was taken to the hospital.

While the medical experts provided contradictory theories

of the victim's injuries, "the question whether to believe the

experts [was] for the jurors." Commonwealth v. Kappler, 416

Mass. 574, 583 (1993). "This is particularly true of experts in

the medical field, who regularly are permitted to testify on the

basis of examination of records and other materials with respect

to an issue in dispute." Commonwealth v. Cowen, 452 Mass. 757,

762 (2008). Here, where the defendant presented expert

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testimony offering an alternative theory for the victim's

injuries, the weight of the competing expert testimony was a

matter for the jury. See id.8

Setting aside the testimony of her own experts, the

defendant argues that Holsapple's testimony on rebleeds

"obviously undermined the Commonwealth's case." Specifically,

while Holsapple testified that no old subdural hematoma was

found during surgery, when asked whether the amount of blood was

consistent with a rebleed, he acknowledged that "[i]t could be."

But Holsapple subsequently qualified this statement by

explaining that "rebleeds . . . tend not to be large acute

subdurals of the type that [the victim] had but it is possible."

The jury could have considered Holsapple's testimony together

with the Commonwealth's experts' testimony and still reasonably

concluded that the victim's injuries were not caused by a

8 This is consistent with our most recent case law considering expert testimony on abusive head trauma. See Commonwealth v. Epps, 474 Mass. 743 (2016); Millien, 474 Mass. 417. In each case, we vacated the underlying conviction and remanded for a new trial where the Commonwealth had presented expert testimony on shaken baby syndrome or abusive head trauma, as the defendant was deprived of a substantial defense based on expert testimony that the child victim's injuries could have been caused by an accidental short fall. See Epps, supra at 748-749, 767-770; Millien, supra at 423-424, 434-438, 442. We reasoned that, given the "heated debate" surrounding these types of diagnoses in the medical community, the jury ought to have heard both sides of that debate, even where the defense experts fell within the minority on that debate, see Epps, supra at 755, 760, and regardless of who would have ultimately prevailed, Millien, supra at 418, 439.

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rebleed. See Commonwealth v. Hinds, 487 Mass. 212, 225 (2021),

S.C., 494 Mass. 681 (2024) ("the determination of the

credibility of [an] expert and the weight to be attributed to

[an] expert's testimony" are questions for jury).

Considering the evidence presented to them, the jury could

have reasonably inferred that the victim's injuries were the

result of the defendant inflicting blunt force on the victim,

and that this constituted a battery that the defendant knew or

should have known endangered the victim's life. See Sheppard,

404 Mass. at 776–777, 779 (affirming involuntary manslaughter

conviction on theory of battery where defendant punched

substantially smaller victim with sufficient force to cause

victim's head to hit pavement, fracturing victim's skull). The

jury also could have determined that inflicting blunt force on

the victim created a high likelihood of substantial harm to the

victim, thereby constituting wanton or reckless conduct. See

Commonwealth v. Pease, 49 Mass. App. Ct. 539, 540-542 (2000)

(affirming involuntary manslaughter conviction on theory of

wanton or reckless conduct where defendant pushed victim, who

fell and hit head, suffering cerebral trauma leading to death).

2. Expert testimony. The defendant next argues that the

judge abused his discretion by admitting expert testimony

regarding abusive head trauma and short falls.

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"The role of expert testimony is to assist jurors in

interpreting evidence that lies outside their common experience"

(citation omitted). Hinds, 487 Mass. at 217. A judge assesses

the admissibility of scientific expert testimony under the

Daubert-Lanigan standard, pursuant to which he or she must make

"a threshold determination that the testimony is both relevant

and sufficiently reliable to go before the jury" (quotation and

citation omitted). Id. at 218. To determine reliability, a

judge may weigh a nonexclusive list of factors, including

"whether the scientific theory or process (1) has been

generally accepted in the relevant scientific community;

(2) has been, or can be, subjected to testing; (3) has been

subjected to peer review and publication; (4) has an

unacceptably high known or potential rate of error; and (5)

is governed by recognized standards" (citation omitted).

Commonwealth v. Camblin, 478 Mass. 469, 475-476 (2017).

However, a judge need not necessarily weigh each factor, as

pursuant to the test established in Frye v. United States, 293

F. 1013, 1014 (D.C. Cir. 1923), "reliability can still be

established by general acceptance alone, without regard to the

other Daubert-Lanigan factors." Commonwealth v. Davis, 487

Mass. 448, 454 (2021), S.C., 491 Mass. 1011 (2023). See

Commonwealth v. Rintala, 488 Mass. 421, 428 (2021). And if the

proposed expert testimony satisfies this standard, the judge may

still exclude expert testimony if its "probative value is

substantially outweighed by the risk of unfair prejudice,

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confusion, or waste of time" (citation omitted). Commonwealth

v. Chism, 495 Mass. 358, 375 (2025). See Mass. G. Evid. § 403

(2026).

We review a judge's decision to admit or exclude expert

testimony for abuse of discretion. See Rintala, 488 Mass. at

425. See also Chism, 495 Mass. at 375. "[A] judge's

discretionary decision constitutes an abuse of discretion where

we conclude the judge made a clear error of judgment in weighing

the factors relevant to the decision, such that the decision

falls outside the range of reasonable alternatives" (quotation

and citation omitted). L.L. v. Commonwealth, 470 Mass. 169, 185

n.27 (2014). The proponent of the expert testimony "bears the

burden of establishing . . . that the methodology or theory

underlying the expert testimony is sufficiently reliable"

(citation omitted). Rintala, supra at 426.

Before analyzing the testimony at issue here, we begin by

reciting the relevant procedural history.

a. Procedural history. As previously noted, the defendant

filed two motions in limine to exclude certain expert testimony.

First, the defendant moved to exclude testimony at trial

regarding abusive head trauma or shaken baby syndrome,9 and

As we have previously noted, because terms like "shaken

9

baby syndrome" focus on a single injury mechanism -- shaking --use of the term "abusive head trauma" has been recommended to

22

requested a Daubert-Lanigan evidentiary hearing on the subject.

As a basis for her motion, she argued that testimony regarding

abusive head trauma and shaken baby syndrome was inadmissible

under Daubert-Lanigan because, among other things, the theory

"is no longer generally accepted in the relevant scientific

community."

Second, the defendant filed a supplemental motion in limine

seeking to exclude use of the term "abusive" head trauma at

trial. In her motion, she argued that an expert diagnosis using

the word "abusive" would reach the ultimate issue of the

defendant's guilt, impermissibly threatening the independence of

the jury's decision.

A Daubert-Lanigan hearing was held on the defendant's

motions. At the hearing, the defendant's expert Galaznik and

the Commonwealth's expert Schwartz testified. Galaznik opined

that "there is no biomechanical, animal, or human experimental

data" confirming that shaking would be "predicted to produce any

primary brain injury, primary subdural bleeding, or primary

retinal hemorrhaging in a . . . [twenty]-pound infant." He also

testified that, according to research, a short fall of "as

little as . . . two to three feet" could be "capable of inducing

subdural bleeding and . . . the findings in this case."

more inclusively account for injuries inflicted on infants and children. See Millien, 474 Mass. at 423 n.7.

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Schwartz explained that abusive head trauma is a medical

diagnosis that is identified through a differential diagnosis

procedure. She also described a 2018 study finding that the

short fall mortality rate for children under five years old is

0.48 per one million annually.10

On the day before trial, the judge issued his order

allowing the defendant's motions in limine in part and denying

them in part. The judge determined that abusive head trauma was

generally accepted as a reliable medical diagnosis and that,

therefore, expert testimony regarding abusive head trauma was

admissible.11 However, he limited the expert witnesses to

stating that the victim's injuries were "consistent with"

abusive head trauma -- not that abusive head trauma "was the

cause" of the victim's injuries. Additionally, he prohibited

the experts from testifying "that short falls cannot cause

[abusive head trauma]."

b. Abusive head trauma. We now consider whether the judge

abused his discretion by allowing the admission of expert

10See Choudhary et al., Consensus Statement on Abusive Head Trauma in Infants and Young Children, 48 Pediatric Radiology 1048, 1052 (2018).

11The judge discussed all five Daubert-Lanigan factors in his order. However, because general acceptance in the relevant community alone continues to be sufficient to determine reliability, see Rintala, 488 Mass. at 428, we only focus on his findings pertaining to this factor.

24

testimony regarding abusive head trauma. In his decision, the

judge concluded that abusive head trauma "is generally accepted

by physicians and the medical community" as a diagnosis that

does not turn upon the presence of a specific set of symptoms or

observations but is instead reached through a differential

diagnosis.12 In reaching this conclusion, the judge relied on

guidance from various organizations and peer-reviewed consensus

statements designating abusive head trauma as a valid medical

diagnosis.13 However, the judge also expressed concerns about

12The judge rejected the characterization of abusive head trauma as requiring a "triad" of symptoms, noting a 2018 study describing the use of this term as misleading, given the complex nature of the diagnosis. See Millien, 474 Mass. at 418 (abusive head trauma presents as "triad" of symptoms -- subdural hematoma, retinal hemorrhages, and encephalopathy). See also Choudhary et al., supra at 1060 ("The term 'triad' is a legal convention that falsely mischaracterizes a complex [abusive head trauma] diagnosis process").

13In his findings, the judge noted that he relied on statements by the American Academy of Pediatrics, the American Academy of Ophthalmology, the American Association of Neurological Surgeons, the Centers for Disease Control and Prevention, and other comparable organizations. See American Association of Neurological Surgeons, Shaken Baby Syndrome (Apr. 2024), https://www.aans.org/patients/conditions-treatments/ shaken-baby-syndrome [https://perma.cc/KZ5B-X6HT]; American Academy of Ophthalmology, Abusive Head Trauma/Shaken Baby Syndrome (2015); Narang et al., American Academy of Pediatrics, Policy Statement, Abusive Head Trauma in Infants and Children (2020); Public Health Agency of Canada & Canadian Paediatric Society, Joint Statement on Traumatic Head Injuries Due to Child Maltreatment: An Update to the Joint Statement on Shaken Baby Syndrome (2020); Royal College of Paediatrics & Child Health, Child Protection Evidence: Systematic Review on Head and Spinal Injuries (Aug. 2019); Centers for Disease Control and Prevention, About Abusive Head Trauma (May 2024), https://www

25

how the jury would understand the term "abusive," which could

suggest that an action was "violent" or "cruel," or that the

actor had a particular state of mind. Further, the judge noted

that whether abuse had actually occurred was a factual question

committed to the jury. Yet, the judge recognized that

"[p]rohibiting use of the term would be hard to implement,

because the medical witnesses on both sides naturally have used

and will use it, the term describes a specific body of

knowledge, there is no obvious, medically accepted alternative,

and there is a great likelihood that witnesses accustomed to

using the term will do so inadvertently even if ordered to avoid

it." Accordingly, he limited experts to testifying that the

victim's injuries were "consistent with" abusive head trauma,

not that abusive head trauma caused the victim's injuries.

The judge did not abuse his discretion by admitting

testimony that the victim's injuries were "consistent with"

.cdc.gov/child-abuse-neglect/about/about-abusive-headtrauma.html [https://perma.cc/VG83-P356]; Choudhary et al., supra; Narang et al., Acceptance of Shaken Baby Syndrome and Abusive Head Trauma as Medical Diagnoses, 177 J. Pediatrics 273 (2016); Narang et al., A Daubert Analysis of Abusive Head Trauma/Shaken Baby Syndrome -- Part II: An Examination of the Differential Diagnosis, 13 Hous. J. Health L. & Pol'y 203 (2013); Narang, A Daubert Analysis of Abusive Head Trauma/Shaken Baby Syndrome, 11 Hous. J. Health L. & Pol'y 505 (2011); Parks et al., Centers for Disease Control and Prevention, Pediatric Abusive Head Trauma: Recommended Definitions for Public Health Surveillance and Research (Apr. 2012).

26

abusive head trauma. On this record, the judge properly

determined that abusive head trauma is generally accepted as a

valid medical diagnosis in the relevant medical community.14

According to the consensus statements presented by the

Commonwealth, numerous national and international medical

societies and organizations recognize abusive head trauma as a

valid medical diagnosis. See Choudhary et al., Consensus

Statement on Abusive Head Trauma in Infants and Young Children,

48 Pediatric Radiology 1048, 1049, 1052 (2018) (reviewing

"[fifteen] major national and international professional medical

societies' and organizations' consensus statements confirming

the validity of the [abusive head trauma] diagnosis"). The

Commonwealth also presented literature indicating that

physicians widely recognize abusive head trauma as a diagnosis.

For example, in one 2016 survey of children's hospital

physicians with over 600 respondents, ninety-three percent of

14We note that courts in other jurisdictions have likewise found that abusive head trauma is a generally accepted diagnosis. See, e.g., Nielsen v. State, 2018 WY 132, ¶ 32 (abusive head trauma "has long been recognized as a clinically valid medical diagnosis" [citation omitted]). See also Commonwealth v. Fernandez, 458 Mass. 137, 150–151 (2010) ("judges may rely on the decisions of other courts as one factor when evaluating the general acceptance of scientific evidence"). But see State v. Nieves, 262 N.J. 161, 238-239 (2025) (in cases of child abuse from shaking without impact, expert testimony regarding shaken baby syndrome and abusive head trauma not sufficiently reliable to go before jury).

27

surveyed physicians indicated that abusive head trauma is a

valid evidence-based diagnosis. See Narang et al., Acceptance

of Shaken Baby Syndrome and Abusive Head Trauma as Medical

Diagnoses, 177 J. Pediatrics 273, 273 (2016). And further,

abusive head trauma is diagnosed "like any other medical

diagnosis, by considering all the information acquired via

clinical history, physical examination, and laboratory and

imaging data." Choudhary et al., supra at 1052.

Although the defendant provided literature describing the

shortcomings of abusive head trauma and shaken baby syndrome

diagnoses,15 these sources do not undermine the judge's

determination that abusive head trauma is a generally accepted

medical diagnosis. First, "[u]nanimity of opinion among the

15See Bache et al., Open Letter on Shaken Baby Syndrome and Courts: A False and Flawed Premise (2015), http://www .argumentcritique.com/special-edition.html [https://perma.cc /WRB3-3D9W] (scientific basis for shaken baby syndrome diagnosis is disputed); Findley et al., Shaken Baby Syndrome, Abusive Head Trauma, and Actual Innocence: Getting It Right, 12 Hous. J. Health L. & Pol'y 229 (2012) (describing ongoing debates regarding shaken baby syndrome and abusive head trauma diagnoses); Guthkelch, Problems of Infant Retino-Dural Hemorrhage with Minimal External Injury, 12 Hous. J. Health L. & Pol'y 201 (2012) (raising various problems with shaken baby syndrome and abusive head trauma diagnoses, including how terms imply mechanism of injury and theory of perpetrator's intent that are not necessarily accurate); Tuerkheimer, The Next Innocence Project: Shaken Baby Syndrome and the Criminal Courts, 87 Wash. U. L. Rev. 1 (2009) (describing scientific debate regarding whether shaking alone can cause symptoms associated with shaken baby syndrome diagnosis).

28

relevant scientists is not essential even under the general

acceptance test." Commonwealth v. Shanley, 455 Mass. 752, 765

(2010), quoting Lanigan, 419 Mass. at 27. Second, the "judge

ha[d] 'broad discretion' to weigh [the Daubert-Lanigan] factors

and to apply varying methods to assess the reliability of the

proffered testimony." Camblin, 478 Mass. at 476, quoting

Palandjian v. Foster, 446 Mass. 100, 111 (2006). Such

discretion was properly exercised here, particularly where the

defendant's sources primarily dispute the possibility that

shaking alone can cause the injuries associated with abusive

head trauma. See, e.g., Bache et al., Open Letter on Shaken

Baby Syndrome and Courts: A False and Flawed Premise (2015),

http://www.argumentcritique.com/special-edition.html

[https://perma.cc/WRB3-3D9W] ("The scientific basis for the

assertion that these injuries are the consequence of

deliberately inflicted violent shaking is highly contentious").

But the diagnosis of abusive head trauma encompasses multiple

mechanisms of head and brain injury, including shaking, blunt

impact, or a combination of causal mechanisms. See Commonwealth

v. Millien, 474 Mass. 417, 423 n.7 (2016) (term "abusive head

trauma" meant to encompass multiple mechanisms of injury). See

also Parks et al., Centers for Disease Control and Prevention,

Pediatric Abusive Head Trauma: Recommended Definitions for

Public Health Surveillance and Research 10 (Apr. 2012) ("abusive

29

head trauma is defined as an injury . . . due to inflicted blunt

impact and/or violent shaking"). The judge thus did not abuse

his discretion in determining that abusive head trauma is

generally accepted by the medical community.

Next, the defendant argues that Schwartz's testimony

regarding abusive head trauma was inadmissible because it did

not assist the jury pursuant to Mass. G. Evid. § 702(a). She

contends that the jury needed no expert assistance to understand

the link between blunt force impact and the victim's injuries,

where the medical examiner had already testified that the victim

died from multiple blunt force impacts. We disagree.

An expert's testimony must "help the trier of fact to

understand the evidence or to determine a fact in issue." Mass.

G. Evid. § 702(a). See Commonwealth v. Ridley, 491 Mass. 321,

326 n.5 (2023). "This condition goes primarily to relevance."

Id. at 326, quoting Daubert, 509 U.S. at 591. "To be relevant,

the proposed evidence need only have a tendency to make a

material fact more or less probable than it would be without the

evidence." Hinds, 487 Mass. at 219.

Here, an expert opinion concerning the mechanism likely to

have caused the victim's injuries was relevant and helpful to a

lay juror who would not understand the significance of injuries

such as subdural hematomas or midline shifts. Schwartz's

testimony on abusive head trauma provided important context for

30

the jury to weigh when assessing key issues in the case. She

described how quickly symptoms of abusive head trauma manifest

in young children, whether abusive head trauma symptoms are

possible without any external signs of trauma, and the

differences between adult and children's brains that make these

injuries possible. She also provided background on the level of

force necessary to inflict a subdural hematoma -- one of the

injuries associated with abusive head trauma -- by explaining

that the required force is beyond that used in "normal" infant

care. Schwartz's medical expertise thus assisted the jury in

understanding the victim's injuries and held important probative

value. Cf. Commonwealth v. Roderiques, 462 Mass. 415, 428

(2012) ("When medical expertise is necessary to aid

understanding evidence, experts may testify as to the cause of a

victim's injuries"); Commonwealth v. Colin C., 419 Mass. 54, 60

(1994) (information concerning behavioral characteristics of

sexual assault and sexual abuse victims "may aid [the jury] in

reaching a decision").

The defendant further contends that the judge erred in

admitting testimony about abusive head trauma because the word

"abusive" "comes close to an opinion on the ultimate issue of

guilt." While an expert may not provide an opinion on the

defendant's innocence or guilt, Roderiques, 462 Mass. at 428,

"[t]here is no prohibition on an expert testifying to an opinion

31

that touches the ultimate issue in a case," Commonwealth v.

Goddard, 476 Mass. 443, 446 (2017). See Mass. G. Evid. § 704.

Schwartz's testimony stayed within these confines. She

testified that the victim's injuries were consistent with

abusive head trauma -- requiring force beyond "normal" child

care -- and were not consistent with an accidental short fall.

In so opining, "[h]er analysis was confined to the mechanism by

which the injuries were suffered but did not speculate as to the

circumstances or ultimate responsibility for those injuries."

Roderiques, 462 Mass. at 429. And she "never offered an opinion

as to the defendant's ultimate innocence or guilt." Id. See

id. at 428-429 (no abuse of discretion in allowing expert to

opine that baby's injuries were "not accidental" and that

certain injuries "could not have been caused by a man stepping

on the child while asleep in a recliner").

When such testimony approaches an ultimate issue of guilt,

"the probative value of the opinion must be weighed against the

danger of unfair prejudice" (citation omitted). Goddard, 476

Mass. at 447. See Mass. G. Evid. § 403. As discussed above,

Schwartz's testimony held significant probative value, as it

provided context regarding the timing, symptoms, and force

associated with the victim's injuries. On the other side of the

scale, there was also a risk of prejudice here. As the judge

noted, particularly where "abusive" is an emotionally charged

32

word that approaches the ultimate opinion, there was a risk that

the jury might use it as a proxy for culpability. See

Commonwealth v. Rodriguez, 437 Mass. 554, 561 (2002) (discussing

possibility that designation of witness as expert could cause

jury to defer to expert's opinion).

Given this risk of prejudice, the judge imposed appropriate

limits to mitigate any prejudicial effect from testimony

regarding abusive head trauma. In his order, he prohibited

experts from stating that abusive head trauma was the cause of

the victim's injuries and instead confined them to stating that

the injuries were "consistent with" abusive head trauma. This

prevented expert witnesses from encroaching on the jury's

ultimate responsibility of determining the defendant's guilt.

Cf. Commonwealth v. Wilson, 441 Mass. 390, 400-401 (2004) (judge

properly admitted expert testimony that hypothetical facts were

"consistent with" possession of marijuana with intent to

distribute); Commonwealth v. Colon, 64 Mass. App. Ct. 303, 312

(2005) (expert may opine that child's vaginal injuries were

"consistent with" penetration). Moreover, the defendant had

multiple opportunities to cure any potential prejudicial effect

through cross-examination of the experts and by providing expert

testimony describing the shortcomings of an abusive head trauma

diagnosis. See Commonwealth v. Mason, 485 Mass. 520, 535 (2020)

(risk of prejudice from witness's testimony mitigated on cross33

examination). Cf. Millien, 474 Mass. at 423-424, 430, 433-434

(defendant prejudiced by counsel's failure to seek funds to

retain expert witness, who could have challenged Commonwealth

expert's opinion that victim's head injuries were caused by

violent shaking rather than short fall). And in the final jury

charge, the judge instructed the jury that, although they could

weigh expert testimony in their fact finding, they were required

to reach their own conclusions on the defendant's guilt or

innocence. See Commonwealth v. Stokes, 440 Mass. 741, 751

(2004), S.C., 460 Mass. 311 (2011) ("We presume the jury follow

the judge's instructions").

Accordingly, the judge did not abuse his discretion in

admitting testimony that the victim's injuries were "consistent

with" abusive head trauma.

c. Short falls. Finally, we examine the judge's ruling on

expert testimony pertaining to short falls. The judge concluded

that there is no general acceptance of the theory that

accidental short falls can never cause symptoms consistent with

abusive head trauma, pointing to studies in the record that at

least supported such a scenario as a rare possibility. See

Commonwealth v. Epps, 474 Mass. 743, 759-760 (2016) (discussing

medical and scientific debate whether accidental short falls can

cause such injuries). Consequently, the judge's order

34

prohibited testimony "that short falls cannot cause [abusive

head trauma]."

The defendant argues that the judge's order was violated

when Shah and Schwartz testified that the victim's injuries were

not consistent with a short fall. When asked whether the

victim's injuries "would likely be caused by a short fall less

than three feet," Shah responded that the victim's injuries

"would not be consistent with that short [of a] fall."

Similarly, Schwartz opined that the victim's subdural injury

could not be caused by a fall from a sitting position. In both

instances, this expert testimony reflected specific analysis of

the victim's injuries, whereas the order prohibited testimony

that short falls, in general, cannot cause abusive head trauma.

The experts' testimony thus did not violate the order.

Conclusion. For the foregoing reasons, we conclude that

the evidence was sufficient to convict the defendant of

involuntary manslaughter. Further, we determine that the judge

did not abuse his discretion by admitting expert testimony that

the victim's injuries were "consistent with" abusive head

trauma.

Judgment affirmed.