It will be noticed that the legal allegations designating the crime used in this indictment are the same as are used in the charge and specifications on which Surratt's co-conspirators were arraigned and tried before the Commission, except that the word "traitorously," there used, is omitted in this indictment. This indictment in its first count charged the prisoner on trial with the murder of Abraham Lincoln. This was done on the principle that when two or more persons conspire together to do an unlawful act, or to do that which is lawful by unlawful means, the act of any one of the parties thus conspiring, in pursuance of said conspiracy becomes the act of all. They are held equally guilty in law. To make this count good, it was only necessary to prove the existence of a conspiracy to do this murder--that it was done by one of the conspirators, and that the person indicted was a member of said conspiracy at the time the murder was committed, and that he aided and abetted and performed his part, whatever that might be, in accomplishing the object of the conspiracy. The second count charges that Surratt and Booth murdered Abraham Lincoln, and that the murder was actually accomplished by the hand of Booth. This implies that they acted together for the accomplishment of the crime and would be made good only by proving the presence of John H. Surratt at the time and place of its commission, and that he was there aiding and abetting Booth in the alleged murder. The third count simply enlarges the conspiracy by designating others known to have been included in its membership, alleging also, that there were still others belonging to it, who were unknown to the jury, and that in pursuance of its object and purpose the murder was done by the hand of one of its members. The fourth count more distinctly and emphatically alleges the combining, confederating, conspiring, and agreeing together of these persons to do this murder, and that it was so done by one of its members, viz., Booth. This would require proof to be made of such combination and agreeing together to commit this crime on the part of the persons named in the indictment; that the crime was perpetrated, and that the prisoner was a member of said conspiracy at the time of its perpetration. It will be remarked that in addition to the word "traitorously," used in the charge and specifications against the members of this conspiracy who were tried before the Commission, the political purpose of the conspiracy, as there alleged, is here omitted. The real purpose of the conspiracy was to aid the existing rebellion in its purpose and effort to overthrow the government by assassinating the President, Vice-President, Secretary of State, and the general in command of the armies of the United States.