In order to reduce the crime from murder to manslaughter it is necessary that it should be shown that the prisoner found the deceased in the very act of adultery with his wife. This does not mean to say that the prisoner must stand by and witness the actual copulative conjunction between the guilty parties. If the prisoner saw the deceased in bed with his wife, or saw him leaving the bed of the wife, or if he found them together in such position as to indicate with reasonable certainty to a rational mind that they had just then committed the adulterous act, it will be sufficient to satisfy the requirements of the law in this regard; and if, under such circumstances, he then and there struck the mortal blow, his offense would amount to manslaughter only. And in principle there can be no difference in the degree of the crime, whether the betrayed husband slays the faithless wife or her guilty paramour. In either event the crime proven has uniformly been held to be, not murder, but manslaughter.
Defendant discovered his wife and another man in the very act of adultery. As his wife and the other man rushed out of the room, defendant fired at the man and killed his wife. The circuit court convicted him for murder. On review, the court reversed defendant's conviction for murder and remanded to the trial court.
Does killing one’s wife upon witnessing her committing adultery constitute adequate provocation to justify reducing the crime from murder to manslaughter?
The court found that the deceased and the other man were surprised by defendant under such conditions and amid such surroundings as to demonstrate with absolute certainty that they were then actually committing adultery. This fact alone, in legal contemplation, was adequate provocation to reduce the grade of the homicide, if then instantly committed, from murder to manslaughter.