In an 1841 Supreme Court case that was a rallying cause for abolitionists, Massachusetts Representative (and former President) John Quincy Adams argued for the rights of West African captives from the Spanish slave ship Amistad. The Africans had mutinied and attempted to sail homeward, but were eventually imprisoned by American authorities. Abolitionists made their case a legal test pitting individual human rights against property claims. Adams argued that racial prejudice underlay the U.S. prosecution of the Africans, and the Supreme Court ruled for their freedom.