The floor debates on slavery at the Constitutional Convention are documented in Part 2 of this series, The Convention Debates. What the floor did not settle, a private agreement did. This episode presents what happened next in the primary record: the bargain Madison documented in his own footnote, the vote of August 25, the fugitive slave clause of August 28, and the three provisions as adopted on September 17, 1787.
James Madison kept the most complete record of the Constitutional Convention's proceedings. His Notes were not published until after his death in 1836. They record the speeches, the motions, the votes, and, in one critical footnote, Madison's own account of the private deal that shaped the outcome on slavery. The full text is at the Yale Avalon Project. Every quote in this episode is from that source.
The slave trade clause was not resolved by the floor debate. It was resolved by a private agreement between Northern and Southern delegates, documented by Madison himself in a footnote to his August 29 entry. The terms of the deal: the South would agree to allow Congress to pass navigation acts by simple majority (which Northern shipping interests wanted), and in exchange, Congress would be prohibited from banning the slave trade until 1808.
An understanding on the two subjects of navigation and slavery, had taken place between those parts of the Union, which explains the vote on the motion depending, as well as the language of Gen. Pinkney & others.
The vote on the slave trade protection clause took place on August 25, 1787. The clause prohibited Congress from banning the importation of enslaved people before 1808, a twenty-year protection from the date of ratification. Madison recorded his own reaction: "Twenty years will produce all the mischief that can be apprehended from the liberty to import slaves. So long a term will be more dishonorable to the National character than to say nothing about it in the Constitution." The vote passed seven states to four.
On August 28, 1787, Pierce Butler and Charles Pinckney of South Carolina moved to require that escaped enslaved people be returned across state lines. Madison recorded the motion and the response directly.
Mr. BUTLER and Mr. PINKNEY moved "to require fugitive slaves and servants to be delivered up like criminals."
Roger Sherman of Connecticut objected, not on moral grounds but on practical ones. Madison recorded: "Mr. SHERMAN saw no more propriety in the public seizing and surrendering a slave or servant, than a horse." Butler withdrew the motion temporarily. It was reintroduced and, in its final form, became Article IV, Section 2, Clause 3 of the Constitution. The word "slave" does not appear in the clause as ratified.
The Constitution signed on September 17, 1787 contained three provisions directly protecting slavery. None uses the words "slave" or "slavery." The language is documented at the National Archives.
"Representatives and direct Taxes shall be apportioned among the several States... by adding to the whole Number of free Persons... three fifths of all other Persons."
Counted enslaved people as three-fifths of a person for apportioning congressional seats and direct taxes. Gave slaveholding states additional political representation based on the size of their enslaved populations. Debated primarily August 8, 1787. Eliminated by the Fourteenth Amendment (1868).
"The Migration or Importation of such Persons as any of the States now existing shall think proper to admit, shall not be prohibited by the Congress prior to the Year one thousand eight hundred and eight."
Prohibited Congress from banning the international slave trade for twenty years from ratification. Debated August 21–25, 1787. The deal between Northern and Southern delegates is documented in Madison's footnote to August 29. Congress banned the trade effective January 1, 1808, the earliest permitted date.
"No Person held to Service or Labour in one State, under the Laws thereof, escaping into another, shall, in Consequence of any Law or Regulation therein, be discharged from such Service or Labour, but shall be delivered up on Claim of the Party to whom such Service or Labour may be due."
Required free states to return escaped enslaved people to their enslavers. Introduced August 28, 1787 by Butler and Pinckney of South Carolina. The Thirteenth Amendment (1865) rendered the clause unenforceable by abolishing slavery.
Madison's Notes record delegates arguing against the slave trade on the Convention floor, and record the same Convention adopting three clauses that protected it. Both facts are in the primary record. The speeches against slavery and the provisions protecting it are in the same document, recorded by the same hand.
This series goes to the primary record. Not to resolve its contradictions, the record does not do that, but to show what was said, what was agreed, and what was adopted, at the level it actually happened. Every claim sourced. Every document linked. The archive is open.