The constitutional argument was not urged as seriously as the foregoing; but it had a considerable place.  On the one hand, it was urged that if the Negroes were forfeited, they were forfeited to the United States government, which could dispose of them as it saw fit;[19] on the other hand, it was said that the United States, as owner, was subject to State laws, and could not free the Negroes contrary to such laws.[20] Some alleged that the freeing of such Negroes struck at the title to all slave property;[21] others thought that, as property in slaves was not recognized in the Constitution, it could not be in a statute.[22] The question also arose as to the source of the power of Congress over the slave-trade.  Southern men derived it from the clause on commerce, and declared that it exceeded the power of Congress to declare Negroes imported into a slave State, free, against the laws of that State; that Congress could not determine what should or should not be property in a State.[23] Northern men replied that, according to this principle, forfeiture and sale in Massachusetts would be illegal; that the power of Congress over the trade was derived from the restraining clause, as a non-existent power could not be restrained; and that the United States could act under her general powers as executor of the Law of Nations.[24]

The moral argument as to the disposal of illegally imported Negroes was interlarded with all the others.  On the one side, it began with the “Rights of Man,” and descended to a stickling for the decent appearance of the statute-book; on the other side, it began with the uplifting of the heathen, and descended to a denial of the applicability of moral principles to the question.  Said Holland of North Carolina:  “It is admitted that the condition of the slaves in the Southern States is much superior to that of those in Africa.  Who, then, will say that the trade is immoral?"[25] But, in fact, “morality has nothing to do with this traffic,"[26] for, as Joseph Clay declared, “it must appear to every man of common sense, that the question could be considered in a commercial point of view only."[27] The other side declared that, “by the laws of God and man,” these captured Negroes are “entitled to their freedom as clearly and absolutely as we are;"[28] nevertheless, some were willing to leave them to the tender mercies of the slave States, so long as the statute-book was disgraced by no explicit recognition of slavery.[29] Such arguments brought some sharp sarcasm on those who seemed anxious “to legislate for the honor and glory of the statute book;"[30] some desired “to know what honor you will derive from a law that will be broken every day of your lives."[31] They would rather boldly sell the Negroes and turn the proceeds over to charity.

The final settlement of the question was as follows:—­