It is contended that the prisoner at the bar could not be a principal, he being in Brown Street, because he could not there render assistance; and you are called upon to determine this case, according as you may be of opinion whether Brown Street was, or was not, a suitable, convenient, well-chosen place to aid in this murder. This is not the true question. The inquiry is not whether you would have selected this place in preference to all others, or whether you would have selected it at all. If the parties chose it, why should we doubt about it? How do we know the use they intended to make of it, or the kind of aid that he was to afford by being there? The question for you to consider is, Did the defendant go into Brown Street in aid of this murder? Did he go there by agreement, by appointment with the perpetrator?[4] If so, every thing else follows. The main thing, indeed the only thing, is to inquire whether he was in Brown Street by appointment with Richard Crowninshield. It might be to keep general watch; to observe the lights, and advise as to time of access; to meet the murderer on his return, to advise him as to his escape; to examine his clothes, to see if any marks of blood were upon them; to furnish exchange of clothes, or new disguise, if necessary; to tell him through what streets he could safely retreat, or whether he could deposit the club in the place designed; or it might be without any distinct object, but merely to afford that encouragement which would proceed from Richard Crowninshield’s consciousness that he was near. It is of no consequence whether, in your opinion, the place was well chosen or not, to afford aid; if it was so chosen, if it was by appointment that he was there, it is enough. Suppose Richard Crowninshield, when applied to to commit the murder, had said, “I won’t do it unless there can be some one near by to favor my escape; I won’t go unless you will stay in Brown Street.” Upon the gentleman’s argument, he would not be an aider and abettor in the murder, because the place was not well chosen; though it is apparent that the being in the place chosen was a condition, without which the murder would never have happened.