In Somerset v Stewart, decided on June 22, 1772, the Court of King’s Bench held that no enslaved person could be seized in England and forcibly shipped abroad for sale, because English law contained no statute or established custom authorizing slavery. Lord Mansfield’s judgment did not abolish slavery in England, and it did not free the thousands of enslaved people already living there. What it did was strip slaveholders of the legal machinery they needed to control enslaved people by force on English soil.1English Heritage. The Somerset v Stewart Case
How the Case Reached the Court
James Somerset had been taken from West Africa, sold into slavery in the American colonies, and purchased there by Charles Stewart, a Scottish customs officer.2Enslaved.org. James Somerset Stewart brought him to England in November 1769. Somerset was baptized as a Christian soon after arriving, and his godparents, Thomas Walkin, Elizabeth Cade, and John Marlow, would prove decisive later.3Lincoln’s Inn Rare Books and Manuscripts Online. Somerset’s Case
In October 1771, after about two years in England, Somerset left Stewart’s household. Stewart’s agents recaptured him weeks later, delivered him in irons to Captain John Knowles aboard the merchant ship Ann and Mary on the Thames, and prepared to ship him to Jamaica for sale.4Famous Trials. The James Sommersett Case (1772) Somerset’s godparents swore statements describing his imprisonment and the ship’s intended destination, and on that basis Lord Mansfield granted a writ of habeas corpus on December 3, 1771. Six days later Knowles produced Somerset before the court.3Lincoln’s Inn Rare Books and Manuscripts Online. Somerset’s Case
Knowles’s formal return to the writ set out Stewart’s position: Somerset was an African slave, lawfully purchased, held under the laws of Virginia and Jamaica, brought to England temporarily, and confined for return to Jamaica after leaving without permission. That return forced the court to decide whether colonial slave law had any force in England when Parliament had passed no statute supporting it.4Famous Trials. The James Sommersett Case (1772)
Lord Mansfield’s Ruling
Mansfield, Chief Justice of the King’s Bench, deliberated for months. Roughly 15,000 enslaved people lived in England at the time, and a broad ruling risked enormous property claims. He reportedly urged the parties to settle. They did not, and on June 22, 1772, he delivered judgment.
He framed the question narrowly: was the reason Knowles gave for holding Somerset legally sufficient? He concluded it was not. His most quoted passage runs: “The state of slavery is of such a nature, that it is incapable of being introduced on any reasons, moral or political; but only positive law. … It is so odious, that nothing can be suffered to support it, but positive law. Whatever inconveniences, therefore, may follow from this decision, I cannot say this case is allowed or approved by the law of England; and therefore the black must be discharged.”1English Heritage. The Somerset v Stewart Case
By “positive law,” Mansfield meant a specific statute or long-established legal custom carrying the force of law. Parliament had passed no such statute, and no ancient English custom supported holding a person as property. The detention had no lawful basis. Somerset walked free.
What the Ruling Actually Decided
The narrowness of the holding matters. The court decided that a slaveholder in England could not seize an enslaved person and detain them for shipment out of the country to be sold. It also confirmed that habeas corpus was available to enslaved people to prevent that kind of seizure and deportation, treating them as persons entitled to the writ rather than as property.1English Heritage. The Somerset v Stewart Case
The ruling did not abolish slavery in England. It did not free other enslaved people living there. It did not make slaveholding itself illegal. Mansfield was careful to avoid ruling on the broader legal status of enslaved people or the full scope of their rights.
What it did in practice was pull out the enforcement mechanism. A slaveholder in England could no longer call on the courts or law enforcement to recapture someone who left their service, and could not chain a person to a ship bound for the Caribbean. The most coercive tools of control became legally unavailable on English soil, and once enslaved people understood that the courts would not drag them back, the practical power of slaveholders in England eroded.
Reaction in the American Colonies
The decision had no direct legal effect outside Britain, but it was closely followed across the empire and especially in the thirteen American colonies.5Wikipedia. Somerset v Stewart Many colonists, and many enslaved people in the colonies, read the ruling as having effectively ended slavery in England, and some enslaved people invoked it in bids for their own freedom. For slaveholding colonists, the case raised the possibility that Parliament might one day legislate against slavery in the colonies as well, feeding grievances that were already building toward revolution.
The Ruling’s Longer Life
Mansfield’s reasoning outlived the specific facts of the case. His insistence that slavery required positive law to exist became a foundation for later abolitionist legal arguments. Britain abolished the transatlantic slave trade in 1807, and the Slavery Abolition Act of 1833 ended slavery throughout most of the British Empire. If slavery had no natural legal standing and could survive only through legislation, then legislation could also destroy it.
The case also expanded the practical reach of habeas corpus. Before Somerset, the writ was associated mainly with political prisoners and criminal defendants. Godparents filing papers on behalf of a man chained in a ship’s hold showed that any person held without lawful authority could demand a judicial hearing, and the principle carried broader force after the ruling.