Fugitive Slave Clause in the context of "Fugitive slaves"

In the United States before 1865, a free state was a state in which slavery and the internal or domestic slave trade were prohibited, while a slave state was one in which they were legal. Between 1812 and 1850, it was considered by the slave states to be politically imperative that the number of free states not exceed the number of slave states, so new states were admitted in slave–free pairs. There were, nonetheless, some slaves in most free states up to the 1840 census, and the Fugitive Slave Clause of the U.S. Constitution, as implemented by the Fugitive Slave Act of 1793 and the Fugitive Slave Act of 1850, provided that a slave did not become free by entering a free state and must be returned to their owner. Enforcement of these laws became one of the controversies that arose between slave and free states.

By the 18th century, slavery was legal throughout the Thirteen Colonies, but at the time of the American Revolution, rebel colonies started to abolish the practice. Pennsylvania abolished slavery in 1780, and about half the states had abolished slavery by the end of the Revolutionary War or in the first decades of the new country's existence, although, depending on the jurisdiction, this did not mean that all slaves became immediately free due to gradual abolition. Vermont — having declared its independence from Britain in 1777 and thus not being one of the Thirteen Colonies — banned slavery in the same year, before being admitted as a state in 1791.

Article Four of the United States Constitution outlines the relationship between the various states, as well as the relationship between each state and the United States federal government. It also empowers Congress to admit new states and administer the territories and other federal lands.

The Full Faith and Credit Clause requires states to extend "full faith and credit" to the public acts, records, and court proceedings of other states. The Supreme Court has held that this clause prevents states from reopening cases that have been conclusively decided by the courts of another state. The Privileges and Immunities Clause requires interstate protection of "privileges and immunities," preventing each state from treating citizens of other states in a discriminatory manner. The Extradition Clause requires that fugitives from justice be extradited on the demand of executive authority of the state from which they flee. Since the 1987 case of Puerto Rico v. Branstad, federal courts may also use the Extradition Clause to require the extradition of fugitives. The Fugitive Slave Clause requires the return of fugitive slaves; this clause was rendered moot by the Thirteenth Amendment, which abolished involuntary servitude, except in the prison system.

Fugitive slaves or runaway slaves were historical terms used in the 18th and 19th centuries to describe individuals who fled the institution of slavery in the United States. Modern historical scholarship often prefers the terms self-emancipated people or freedom seekers to acknowledge the active role these individuals took in claiming their own liberty.

The history of self-emancipation is linked to two federal laws that established the right of retrieval: the Fugitive Slave Act of 1793 and the Fugitive Slave Act of 1850. The legal status of a person escaping slavery was initially addressed in the United States Constitution's Fugitive Slave Clause (Article IV, Section 2, Clause 3), which mandated the return of such individuals to the party claiming ownership. This legal framework, in tension with resistance efforts like the Underground Railroad and Northern "personal liberty laws," intensified the sectional conflict between slaveholding states and free states, contributing significantly to the causes of the American Civil War.

The Fugitive Slave Act of 1793 was an Act of the United States Congress to give effect to the Fugitive Slave Clause of the U.S. Constitution (Article IV, Section 2, Clause 3), which was later superseded by the Thirteenth Amendment, and to also give effect to the Extradition Clause (Article 4, Section 2, Clause 2). The Constitution's Fugitive Slave Clause guaranteed a right for a slaveholder to recover an escaped slave. The subsequent Act, "An Act respecting fugitives from justice, and persons escaping from the service of their masters", created the legal mechanism by which that could be accomplished.