Com. v. Distefano, B., 236 A.3d 93

On Feb. 3, 2017, after a house party, DiStefano, King, and victim Caleb Zweig, all intoxicated, got into an altercation; King saw DiStefano kneeling over Zweig with hands near chest/neck for only a few seconds before King pulled him off.
Zweig was found unresponsive, taken to hospital, and died shortly after; autopsy found only a scalp hemorrhage and no definitive fatal anatomic injury.
Forensic pathologist Dr. Ashley Zezulak opined the cause of death was "asphyxiation, secondary to presumed chokehold and chest compression," but described that opinion as partly investigative and not definitive.
DiStefano was initially charged with aggravated assault and homicide; the trial court dismissed both on habeas, the Superior Court affirmed dismissal of the homicide charge but reinstated aggravated assault and remanded.
On remand DiStefano moved in limine to exclude evidence of Zweig’s death and any evidence that DiStefano caused the death; the trial court allowed proof of death (and the scalp hemorrhage) but barred causation evidence.
The Commonwealth appealed the pretrial exclusion; the Superior Court reversed, holding evidence on causation (including Dr. Zezulak’s expert opinion) is admissible and its weight is for the jury.

Issue	Commonwealth's Argument	DiStefano's Argument	Held
Admissibility of evidence tying defendant to victim’s death at trial on aggravated assault (serious bodily injury / substantial risk of death)	Evidence of causation is relevant to prove serious bodily injury and recklessness and is probative of aggravated assault elements	Causation evidence is irrelevant and unduly prejudicial given the homicide dismissal and the inconclusive autopsy; Commonwealth offered no supplemental proof	Reversed exclusion. Evidence relating to causation is relevant and admissible; jury decides weight and credibility
Admissibility of an inconclusive expert opinion on cause of death	Expert opinion need not be conclusive to be relevant or admissible; probative value persists despite uncertainty	The expert’s opinion is too speculative and would unfairly prejudice the defense	Court held expert testimony admissible even if inconclusive; any shortcomings affect weight, not admissibility

Commonwealth v. Cook, 952 A.2d 594 (Pa. 2008) (establishes relevance as threshold for evidence admission)
Commonwealth v. Zugay, 745 A.2d 639 (Pa. Super. 2000) (standard of review for motions in limine akin to evidence suppression review)
Commonwealth v. Kane, 188 A.3d 1217 (Pa. Super. 2018) (abuse of discretion standard for evidentiary rulings)
Commonwealth v. Patrick, 933 A.2d 1043 (Pa. Super. 2007) (explains aggravated assault recklessness and "substantial risk of death" as serious bodily injury)
Commonwealth v. Hawk, 709 A.2d 373 (Pa. 1998) (expert testimony need not be conclusive to be admissible)
Commonwealth v. Minerd, 753 A.2d 225 (Pa. 2000) (inconclusive expert findings do not automatically bar testimony)
Commonwealth v. Crews, 640 A.2d 395 (Pa. 1994) (expert relevancy and admissibility principles cited by Hawk)
Commonwealth v. Akhmedov, 216 A.3d 307 (Pa. Super. 2019) (definition of relevance and materiality for evidence)