C O M P A R AT I V E S T U D Y Commonwealth v. Webster (1850) The Supreme Court of Massachusetts case Commonwealth v. Webster390 has endured to this day for the instruction given to the jury by Chief Justice Lemuel Shaw, but it was nonetheless infamous at the time due to the public profile of the victim and the accused. Dr. John Webster, a professor of chemistry at Harvard University, was accused of murdering his colleague, Dr. George Parkman, who was a well-known figure around Boston.391 Webster discussed the level of certainty necessary to warrant a conviction based on circumstantial evidence and provided a definition of the reasonable doubt standard.392 The Court noted that this was a case “to be proved, if proved at all, by circumstantial evidence.”393 It indicated that because “[c]rimes are secret” it becomes necessary to use “all other modes of evidence besides that of direct testimony, provided such proofs may be relied on as leading to safe and satisfactory conclusions.”394 However, “great care and caution ought to be used in drawing inferences from proved facts,” as “[t]he common law appeals to the plain dictates of common experience and sound judgment; and the inference to be drawn from the facts must be a reasonable and natural one, and, to a moral certainty…. It is not sufficient that it is probable only: it must be reasonable and morally certain.”395 The Court then added that “inferences drawn from independent sources, different from each other, but tending to the same conclusion, not only support each other but do so with an increased weight.”396 “[A]ll the facts proved must be consistent with each other, and with the main fact sought to be proved….”397 Thus, if any fact “necessary to the conclusion is wholly inconsistent with the hypothesis of the guilt of the accused, it breaks the chain of circumstantial evidence upon which the inference depends; and, however, plausible or apparently conclusive the other circumstances may be, the charge must fail.”398 Furthermore, “[i]t is not sufficient that [the circumstances] create a probability, though a strong one; and if, therefore, assuming all the facts to be true which the evidence tends to establish, they may yet be accounted for upon any hypothesis which does not include the guilt of the accused, the proof fails.”399 Commonwealth v. Webster, 59 Mass. 295 (1850) (hereinafter, “Webster”). Webster, at 295, 300. 392 Webster, at 310-20. 393 Webster, at 310. 394 Webster, at 311, citing Edward Hyde East, A Treatise of the Pleas of the Crown c. 5, § 11 (P. Byrne 1806). 395 Webster, at 312-13 (emphasis added). 396 Webster, at 317. 397 Webster, at 318. 398 Webster, at 318-19. 399 Webster, at 319. 390 391 95