Chases Points, see this link

http://www.usconstitution.net/consttop_slav.html

Other examples of anti-slavery messages abound from the late 1700's. They illustrate the feelings of some, but those feelings cannot be seen in the product of their works at creating a government. Despite the freedoms demanded in the Declaration and the freedoms reserved in the Constitution and the Bill of Rights, slavery was not only tolerated in the Constitution, but it was codified.

The Constitution has often been called a living tribute to the art of compromise. In the slavery question, this can be seen most clearly. The Convention had representatives from every corner of the United States, including, of course, the South, where slavery was most pronounced. Slavery, in fact, was the backbone of the primary industry of the South, and it was accepted as a given that agriculture in the South without slave labor was not possible. Though slaves were not cheap by any measure, they were cheaper than hiring someone to do the same work. The cultivation of rice, cotton, and tobacco required slaves to work the fields from dawn to dusk. If the nation did not guarantee the continuation of slavery to the South, it was questioned whether they would form their own nation.

Slavery is seen in the Constitution in a few key places. The first is in the Enumeration Clause, where representatives are apportioned. Each state is given a number of representatives based on its population - in that population, slaves, called "other persons," are counted as three-fifths of a whole person. This compromise was hard-fought, with Northerners wishing that slaves, legally property, but uncounted, much as mules and horses are uncounted. Southerners, however, well aware of the high proportion of slaves to the total population in their states, wanted them counted as whole persons despite their legal status. The three-fifths number was a ratio used by the Congress in contemporary legislation and was agreed upon with little debate.

In Article 1, Section 9, Congress is limited, expressly, from prohibiting the "Importation" of slaves, before 1808. The slave trade was a bone of contention for many, with some who supported slavery abhorring the slave trade. The 1808 date, a compromise of 20 years, allowed the slave trade to continue, but placed a date-certain on its survival. Congress eventually passed a law outlawing the slave trade that became effective on January 1, 1808.

The Fugitive Slave Clause is the last mention. In it, a problem that slave states had with extradition of escaped slaves was resolved. The laws of one state, the clause says, cannot excuse a person from "Service or Labour" in another state. The clause expressly requires that the state in which an escapee is found deliver the slave to the state he escaped from "on Claim of the Party."