"The Slavery Compromises
Years before the Constitutional Convention in Philadelphia in 1787, Thomas Jefferson, a slaveowner himself, admitted the horrible nature of slavery: In his 1782 "Notes on Virginia" he made a prophetic statement in regard to U.S. slavery: "Indeed I tremble for my country when I reflect that God is just."
Recall that in the "Great Compromise," it was determined that representation in the House of Representatives would be based on the population of each state. After the convention approved the Great Compromise, Madison wrote: "It seems now to be pretty well understood that the real difference of interests lies not between the large and small but between the northern and southern states. The institution of slavery and its consequences form the line of discrimination." This division over slavery led to the "3/5 Compromise."
Of the 55 Convention delegates, about 25 (almost half!) owned slaves. The delegates from Southern (slave) states wanted to counts slaves as part of their population. This would give the Southern states additional representatives in the U.S. House of Representatives. Delegates from the Northern (Free) states strongly opposed this, arguing that if slaves had no rights to vote (or any other rights of citizenship) then the South should not be given additional representatives in the House. Also, the North feared that counting slaves as part of the South's population would allow the South to have enough representatives in the House to out-vote the North on issues regarding slavery. The South likewise feared that not counting slaves as part of their population would give the South too few representatives in the House, thus allowing the North to out-vote the South on issues regarding slavery. The compromise they reached would arbitrarily count each slave as 3/5 of a person. Thus, neither North nor South fully got their way, as slaves were counted in part toward population when determining how many representatives the free whites should have in the House of Representatives. Hence the name "3/5 compromise." Not wanting to put the word "slave" in the Constitution, the delegates agreed the Constitution would state that population would be determined by counting the number of "free Persons . . . plus three-fifths of all other Persons . . ." Of course, if one is an "other person" rather than a free person, obviously the "other person" must be "not free"; in other words, a slave.
The North and South also divided over whether the new national legislature (Congress) would be able to regulate (and thus perhaps outlaw) slavery. The North wanted the legislature to be able to regulate slavery, and of course the South did not want the legislature to have this power.
The Southern delegates used both economic and racial justifications for slavery. During the South Carolina Ratifying convention, Charles Cotesworth Pinckney repeated his argument for continuing slavery: "While there remained one acre of swamp-land uncleared of South Carolina, I would raise my voice against restricting the importation of negroes. I am . . . thorougly convinced . . . that the nature of our climate, and the flat, swampy situation of our country, obliges us to cultivate our lands with negroes, and that without them South Carolina would soon be a desert waste." (4 Jonathan Elliott, Debates in the Several State Conventions 273, 285 (1891)) Other Southerners were evern more direct racial supremacists, arguing that if slaves became free, they would engage in countless violent crimes against whites, and would also interbreed with whites, thus "polluting" the white race.
The delegates from the Northern free states believed that concessions on slavery were the price for the support of southern delegates for a strong central government. They were convinced that if the Constitution restricted the slave trade, some Southern states would refuse to join the Union. The delegates at the Constitutional Convention finally agreed that Congress would be prohibited from regulating the international slave trade (i.e. imports of slaves from foreign countries) for 20 years, but after that time it could prohibit it. Again, not wanting to use the word "slavery, the delegates agreed the Constitution would state: "the 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." (Notice 1808 would be 20 years after ratification). To what degree domestic slavery could be regulated after that time was simply left an open, undecided question. Basically the delegates agreed they could not agree, so put off the issue for (at least) 20 years. But by sidestepping the slavery issue, the framers simply were delaying the inevitable conflict over slavery.
However, the Southern states' agreement to the ending of the international import of slaves was based not on morality, but on simple economics and politics. Politically, Southern whites feared if the slave population continued to increase in relative proportion to the white population, eventually the slave population would become so large, it would be uncontrollable by the white population and would rebel and even take revenge on their former masters. Economically, states with a large existing slave population such as Virginia would see the value of their slaves increase if the importation of additional slaves was halted. So even the Southern states went along with the ban on new importation of slaves, but for purely selfish reasons and not out of any moral opposition to slavery.
Finally, the Southern states insisted that escaped slaves be returned to them, otherwise slaves would have a strong incentive to try to escape to a Northern state where they could be free. So, the Northern delegats agree to a clause in the Constitution dealing with fugitive slaves, required runaway slaves to be returned their owners upon demand by the owner. Once again not wanting to use the word "slave," the Fugitive Slave Clause substituted "person held to service or labour" in place of the word "slave": "No Person held to Service or Labour in one State, . . . , escaping into another, shall . . . 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."
Some of the delegates, however, such as Gouverneur Morris of Pennsylvania, were outraged that any compromise was reached. During the Convention, on August 8, he gave what came to be called his famous "Curse of Heaven" speech, one of the most stirring speeches at the Constitutional Convention. Madison's notes for that day record "Gvrnr. Morris" as stating: "He never would concur in upholding domestic slavery. It was a nefarious institution. It was the curse of heaven on the States where it prevailed. . . . Upon what principle is it that the slaves shall be computed in representation? Are they men? Then make them Citizens and let them vote. Are they property? Why is no other property included? . . .The admission of slaves into the Representation when fairly explained comes to this: that the inhabitant of Georgia and S.C. who goes to the Coast of Africa, and in defiance of the most sacred laws of humanity tears away his fellow creatures from their deearest connections and damns them to the most cruel bondages, shall have more votes in a Govt. instituted for the protection of the rights of mankind, than the Citizen of Pa. or N. Jersey who views with a laudable horror, so nefarious a practice." Gouverneur Morris went on to contrast the prosperity and human dignity of free states and territories with "the misery and poverty" of slave states.
On Saturday, August 25, John Dickenson moved to make the slavery clauses more explicit by changing "persons" to "slaves." Several delegates objected to this. Madision records his own objection: "Mr. Madison thought it wrong to admit in the Constitution the idea that there could be property in men." A draft of notes that Dickinson made for a speech at the convention (but which he apparently never gave) arguing in favor of using the world "slave" included this statement: "The omitting the Word will be regarded as an Endeavor to conceal a principle of which we are ashamed."