The Supreme Court of Pennsylvania has held that the medical causation needed in a homicide case must be established "beyond a reasonable doubt," as opposed to "reasonable degree of medical certainty."
Commonwealth v. Embry, 441 Pa. 183, 272 A.2d 178 (1971).
Bart M. Beier,
Criminal Law - Homicide - Felony Murder - Causation - Degree of Proof,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol9/iss3/19