The Amistad Committee recognized the need for a public figure of the highest standing to plead the cause of the African captives before the United States Supreme Court. The abolitionists persuaded former President John Quincy Adams to lead the defense. At seventy-three, and thirty years out of legal practice, the ex-President was reluctant to accept the case, lest he should jeopardize the lives of the Africans by failing to win. He wrote in his diary:

The world, the flesh, and all the devils in hell are arrayed against any man who now in this North American Union shall dare to join the standard of Almighty God to put down the African slave trade; and what can I, upon the verge of my 74^th birthday, with a shaken hand, a darkening eye, a drowsy brain, and with my faculties dropping from me one by one as the teeth are dropping from my head -- what can I do for the cause of God and man, for the progress of human emancipation, for the suppression of the African slave-trade? Yet my conscience presses me on; let me but die upon the breach.

Thus, Adams accepted the sensational case that came to be called "the trial of one President by another." Attorney Baldwin prepared an elaborate defense and opened the case, but on February 24, "Old Man Eloquent," as Adams came to be called thereafter, addressed the Court for a total of four and a half hours. On March 9, 1841, the United States Supreme Court issued its final verdict in the Amistad Case -- the captives were free! Adams sent word at once to Lewis Tappan, the principal leader of the Amistad Committee: "Thanks -- Thanks in the name of humanity and of justice, to YOU."