"After addressing the bench, the case was opened for the prosecution by Mr. Pitcairn, as follows:
"Gentlemen of the Jury:
"The crime imputed to the prisoner at the bar is that of wilful murder, effected by means and in a manner most abhorred. Such an accusation naturally excites the indignation of honest minds against the criminal. I will not endeavor to increase it, and it is your duty to resist it and to investigate and determine the case wholly upon the evidence which will be placed before you.
"On the night of the twenty-third of February, 1788, John Stewart Aglionby Montrose, Duke of Borthwicke, was found, between the hours of midnight and one of the morning, dead in a desk-chair, in a chamber on the ground floor of Stair House, near Edinburgh, by Lord Stair and his serving-men, Huey MacGrath, John Elliott, and James MacColl. The window by the late duke it will be proven was wide open, forming an easy entrance from outside; a pistol, the property of the accused, was found lying by the chair upon which the duke sat, and a wound above the temple of the deceased was discovered, made by a bullet similar to those used in the pistol before mentioned.
"It will be proven by testimony of such a character and from such a source as to render it singularly forcible, that on the morning of the day previous to the night of the murder the accused had threatened the duke's life, applying vile and scurrilous names to the deceased; repeating these threats several times and in various forms.
"It will be proven that there had existed for the accused one of the most powerful incentives to murder known, in the fact that the late duke and he loved, and had loved for some time past, the same lady, Nancy, daughter to Lord Stair; that both had addressed her in marriage, and that in September last the quarrel between them rode so high that a meeting was arranged between the late duke and the accused; and there will be testimony to show that the duel was averted by the late duke's apologizing to Mr. Carmichael, a course urged upon him by the lady herself.
"It will be proven that in October past, after a bitter quarrel with Miss Stair, the accused espoused in a hasty (and in a person of his rank and station), unseemly manner, his mother's cousin, Miss Isabel Erskine; that since that time he has been little in her presence, leaving her alone at the time when a woman most needs the comfort and support of a husband's presence, and paying marked attentions, both in public and private, to the first lady of his choice.
"It will be proven that on the day preceding the murder there was published in an Edinburgh paper called The Lounger the news that an engagement of marriage had been contracted between the late John Stewart Aglionby Montrose, Duke of Borthwicke, Muir, etc., and Mistress Nancy Stair, only daughter of John Stair, Lord of Stair and Alton in the Mearns.
"It will be proven that immediately upon reading this the accused came directly to Stair, and after entering unannounced into the room where the lady was sitting, asked her if the tale were true, calling the late duke a thiever from the poor, a seducer of women, a man drenched in all manner of villainy, and one whom he would rather see her dead than married to. That he had declared that he still loved and had always loved her, that his marriage was but the result of a crazy jealousy, and besought her to promise him that she would never marry the duke. It will be proven by two competent witnesses that upon her refusing to do this, the accused had cried out, 'I will save you the promising, for I swear he shall never live to marry you.'
"It will be proven by a physician of repute that within ten minutes of the time of the murder the accused was seen, hatless, walking very fast or running away from Stair House toward his own home of Arran, and this along a very secluded and unusual path.