In conformity with principle and with authority then, the prisoner at the bar was neither legally nor actually present at Blennerhassett's island; and the court is strongly inclined to the opinion that without proving an actual or legal presence by two witnesses, the overt act laid in this indictment cannot be proved.
But this opinion is controverted on two grounds.
The first is, that the indictment does not charge the prisoner to have been present.
The second, that although he was absent, yet if he caused the assemblage, he may be indicted as being present, and convicted on evidence that he caused the treasonable act.
The first position is to be decided by the indictment itself.... The court understands it to be directly charged that the prisoner did assemble with the multitude and did march with them.... The charges of this special indictment therefore must be proved as laid, and no evidence which proves the crime in a form substantially different can be received....
But suppose the law to be as is contended by the counsel for the United States. Suppose an indictment, charging an individual with personally assembling among others and thus levying war, may be satisfied with the proof that he caused the assemblage. What effect will this law have upon this case?
The guilt of the accused, if there be any guilt, does not consist in the assemblage; for he was not a member of it. The simple fact of assemblage no more affects one absent man than another.
His guilt then consists in procuring the assemblage, and upon this fact depends his criminality. The proof relative to the character of an assemblage must be the same whether a man be present or absent. In general, to charge any individual with the guilt of an assemblage, the fact of his presence must be proved: it constitutes an essential part of the overt act.
If then the procurement be substituted in the place of presence, does it not also constitute an essential part of the overt act? must it not also be proved? must it not be proved in the same manner that presence must be proved?
If in one case the presence of the individual make the guilt of the assemblage his guilt, and in the other case the procurement by the individual make the guilt of the assemblage his guilt, then presence and procurement are equally component parts of the overt act, and equally require two witnesses.