The Unconstitutionality of Slavery is an 1845 abolitionist essay written by the American abolitionist Lysander Spooner. In it, Spooner responds to Garrisonian abolitionists and proslavery theorists who argued that slavery was supported by the United States Constitution. Spooner claims that slavery is unconstitutional and cites natural law, colonial charters, and American founding documents to argue that there is no legal basis for the existence of slavery in the United States and that Congress is obligated to prohibit it.
Spooner was an anarchist who argued that the authority of the courts was derived from fundamental principles of justice and universal human rights. He cites the precedent established in Somerset v Stewart that slavery is incompatible with liberty and cannot exist absent positive legal sanction. Spooner notes that contrary to this principle, the Articles of Confederation, the several state constitutions, and the 1787 federal constitution do not refer to slavery directly; the Declaration of Independence, meanwhile, implicitly proscribes slavery by recognizing life, liberty, and the pursuit of happiness as self-evident natural rights. Spooner rejects appeals to original intent concerning the historical context for constitutional provisions generally understood to address slavery, arguing that laws must be interpreted according to the ordinary meaning of the text. He concludes that there is no legal basis for slavery in the United States and that the Guarantee Clause requires Congress to enforce emancipation.
