Great Britain in her negotiations with other powers had concluded treaties with Spain, Portugal, and the Netherlands, in which, without constituting the crime as piracy or classing it with crimes of that denomination, the parties had conceded to the naval officers of each other the right of search and capture of the vessels of either that might be engaged in the slave trade, and had instituted courts consisting of judges, subjects of both parties, for the trial of the vessels so captured.

In the negotiations with the United States Great Britain had earnestly and repeatedly pressed on them the adoption of similar provisions.  They had been resisted by the Executive on two grounds:  One, that the constitution of mixed tribunals was incompatible with their Constitution; and the other, that the concession of the right of search in time of peace for an offense not piratical would be repugnant to the feelings of the nation and of dangerous tendency.  The right of search is the right of war of the belligerent toward the neutral.  To extend it in time of peace to any object whatever might establish a precedent which might lead to others with some powers, and which, even if confined to the instance specified, might be subject to great abuse.

Animated by an ardent desire to suppress this trade, the United States took stronger ground by making it, by the act above referred to, piratical, a measure more adequate to the end and free from many of the objections applicable to the plan which had been proposed to them.  It is this alternative which the Executive, under the sanction and injunctions above stated, offered to the British Government, and which that Government has accepted.  By making the crime piracy the right of search attaches to the crime, and which when adopted by all nations will be common to all; and that it will be so adopted may fairly be presumed if steadily persevered in by the parties to the present convention.  In the meantime, and with a view to a fair experiment, the obvious course seems to be to carry into effect with every power such treaty as may be made with each in succession.

In presenting this alternative to the British Government it was made an indispensable condition that the trade should be made piratical by act of Parliament, as it had been by an act of Congress.  This was provided for in the convention, and has since been complied with.  In this respect, therefore, the nations rest on the same ground.  Suitable provisions have also been adopted to protect each party from the abuse of the power granted to the public ships of the other.  Instead of subjecting the persons detected in the slave trade to trial by the courts of the captors, as would be the case if such trade was piracy by the laws of nations, it is stipulated that until that event they shall be tried by the courts of their own country only.  Hence there could be no motive for an abuse of the right of search, since such abuse could not fail to terminate to the injury of the captor.