The Northwest Ordinance abolishes slavery in the Northwest Territory above the Ohio River, which includes the present-day states of Ohio, Indiana, Illinois, Michigan, and Wisconsin.

The U.S. Constitution is drafted in Philadelphia. The document does not explicitly mention slavery. However, four different parts of the Constitution reflect a compromise on the issue. First, representation in the House is in proportion to the sum of "free persons" and "three-fifths" of "all other persons," (i.e., slaves). Article I, Section 9 includes a "migration or importation" clause that prohibits the slave trade from being banned before 1808 but nevertheless provides that a tax May be levied on imported slaves. The Fugitive Slave Clause of Article IV, Section 3 provides that "Person[s] held to Service or Labour," (i.e., slaves), escaping from one state shall be delivered to the party "to whom such Service or Labour May be due." Finally, Article V makes the slave trade clause unamendable.