to hold the law for the recovery of fugitive slaves as of no validity, and to defy its execution.  Such are some of the representations that have been made in my hearing, and in regard to which, it has become your duty, as the Grand Inquest of the District, to make legal inquiry.  Personally, I know nothing of the facts, or the evidence relating to them.  As a member of the Court, before which the accused persons may hereafter be arraigned and tried, I have sought to keep my mind altogether free from any impressions of their guilt or innocence, and even from an extra-judicial knowledge of the circumstances which must determine the legal character of the offence that has thus been perpetrated.  It is due to the great interests of public justice, no less than to the parties implicated in a criminal charge, that their cause should be in no wise and in no degree prejudged.  And in referring, therefore, to the representations which have been made to me, I have no other object than to point you to the reasons for my addressing you at this advanced period of our sessions, and to enable you to apply with more facility and certainty the principles and rules of law, which I shall proceed to lay before you.

If the circumstances, to which I have adverted, have in fact taken place, they involve the highest crime known to our laws.  Treason against the United States is defined by the Constitution, Art. 3, Sec. 3, cl. 1, to consist in “levying war against them, or adhering to their enemies, giving them aid and comfort.”  This definition is borrowed from the ancient Law of England, Stat. 25, Edw. 3, Stat. 5, Chap. 2, and its terms must be understood, of course, in the sense which they bore in that law, and which obtained here when the Constitution was adopted.  The expression, “levying war,” so regarded, embraces not merely the act of formal or declared war, but any combination forcibly to prevent or oppose the execution or enforcement of a provision of the Constitution, or of a public Statute, if accompanied or followed by an act of forcible opposition in pursuance of such combination.  This, in substance, has been the interpretation given to these words by the English Judges, and it has been uniformly and fully recognized and adopted in the Courts of the United States. (See Foster, Hale, and Hawkins, and the opinions of Iredell, Patterson, Chase, Marshall, and Washington, J.J., of the Supreme Court, and of Peters, D.J., in U.S. vs.  Vijol, U.S. vs.  Mitchell, U.S. vs.  Fries, U.S. vs.  Bollman and Swartwout, and U.S. vs.  Burr).

The definition, as you will observe, includes two particulars, both of them indispensable elements of the offence.  There must have been a combination or conspiring together to oppose the law by force, and some actual force must have been exerted, or the crime of treason is not consummated.  The highest, or at least the direct proof of the combination may be found in the declared purposes