"The Unconstitutionality of Slavery" by Lysander Spooner is an abolitionist essay written in 1845. Challenging both proslavery advocates and fellow abolitionists who believed the Constitution supported slavery, Spooner argues the opposite case. Drawing on natural law, colonial charters, and founding documents, he contends that slavery has no legal basis in America and that Congress must abolish it. His radical constitutional interpretation proved highly influential among political abolitionists, though Spooner's anarchist principles kept him from joining their movements. (This is an automatically generated summary.)