Commonwealth v. Eddy

73 Mass. 583

• Court: Massachusetts Supreme Judicial Court
• Decided: November 15, 1856
• Status: Published

Opinion

Upon this last point the jury were instructed as follows by

Metcalf, J.

The burden is on the Commonwealth to prove all that is necessary to constitute the crime of murder. And as that crime can be committed only by a reasonable being—a person of sane mind—the burden is on the Commonwealth to prove that the defendant was of sane mind when he committed the act of killing. But it is a presumption of law, that all men are of sane mind; and that presumption sustains the burden of proof, unless it is rebutted and overcome by satisfactory evidence to the contrary. In order to overcome this presumption of law, and shield the defendant from legal responsibility, the burden is on him to prove, to the satisfaction of the jury, by a preponderance of the whole evidence in the case, that, at the time of committing the homicide, he was not of sane mind. This is not only required by the general rule of law, but is distinctly implied in the provision of the Rev. Sts. c. 137, § 12, that “ when any person indicted for an offence shall, on trial, be acquitted by the jury, by reason of insanity, the jury, in giving their verdict of not guilty, shall state that it was given for such cause.”

This same legal doctrine may be stated in another form of words. The law infers, from the fact that a prisoner is a human being, of sufficient age to be deemed capable of committing crimes, the further fact that he is a reasonable being, that is, that he is of sane mind. And proof of the former fact is sufficient evidence of the latter, until the latter is disproved by the preponderance of evidence; and the burden of thus disproving it is on the prisoner. Verdict, guilty.