U.S. Constitution and Acts


Before the American Revolution, both the colonies and Great Britain regulated the African slave trade to what became the United States. The British government gave special protection to the Royal African Company, which brought more Africans slaves to the American colonies than any other single entity. The slave trade was an important part of Britain's mercantile policy: it collected taxes on the slaves while colonial governments both taxed them and occasionally sought to limit their arrivals.

After the Stono Rebellion (1739), South Carolina suspended the trade for a few years because its leaders believed that large numbers of freshly imported Africans would undermine the safety of the colony. Then in 1751 South Carolina imposed a special tax on foreign slaves to slow the trade and, nine years later, once again banned it altogether because leaders of the colony still feared the growing number of African-born slaves. The royal authorities disallowed the law. But in 1764 the colony levied new taxes on African-born slaves because, as the legislature noted, their rising number "may prove of the most dangerous consequence."

Shortly before the Revolution, Virginia also tried to ban the trade, not for prudential reasons but to prevent the outflow of capital from the colony. Virginians attempted to use prohibitive taxes to discourage the trade, but the Crown overruled this law, because the slave trade was vital to the British economy and because the Royal African Company had powerful patrons in the government.

The Slave Trade and the Revolution

In his Summary View of the Rights of British America (1774), Thomas Jefferson asserted, somewhat disingenuously, that Virginians favored the "abolition of domestic slavery" and that as the first step toward this end, "it is necessary to exclude all further importations from Africa." He complained, however, that "our repeated attempts to effect this by imposing duties which might amount to a prohibition, have been hitherto defeated by his majesty's negative." In his first draft of the Declaration of Independence, Jefferson condemned the Crown in more forceful language, asserting that the king had "waged cruel war against human nature itself, violating its most sacred rights of life and liberty" by perpetuating the African slave trade. Calling it "piratical warfare," Jefferson asserted that "a CHRISTIAN king of Great Britain" was so "Determined to keep open a market where MEN" were bought and sold that he used his "negative" to suppress "every legislative attempt to prohibit or to restrain this execrable commerce."

The Continental Congress removed Jefferson's tirade from the Declaration, in part because it simply did not ring true. The colonists, for the most part, had been willing and eager purchasers of slaves. Nor is there any evidence that either Jefferson or any of the other leaders of Virginia had any interest in actually ending slavery. Virginia's attempt to ban the trade was purely economic, and not based on any moral opposition to slavery. Similarly, the Crown's refusal to allow them to limit or end the trade was economic.

During the Revolution, all of the new states banned or suspended the international slave trade. Most slaves arrived on English ships, and even those on American ships were purchased from agents of the Royal African Company stationed on the west coast of Africa. Thus, all the colonies (which soon became the states) banned the African slave trade as part of their overall policy of refusing to import anything from Britain. The "non-important" movement was an attempt to cut all economic ties with Britain. Since most slaves were brought in by British ships, and virtually all were purchased from the British on the coast of Africa, a ban on the trade was an important part of the colonists' general policy not to trade with Britain.

In some of the northern colonies, abolition of the slave trade had a moral as well as an economic basis. Opposition to slavery was growing, and during or immediately after the Revolution, five states would either end it outright (Massachusetts and New Hampshire) or pass gradual abolition acts (Pennsylvania, Rhode Island, and Connecticut) that would lead to a relatively speedy end to slavery. In those states, a ban on the international slave trade was consistent with growing opposition to slavery itself. In the remaining new states, where slavery was central to the economy, opposition to the trade was economic and political, but not essentially moral. After the Revolution, South Carolina reopened its international trade, but then suspended it in 1785 because of the ongoing depression in the state. Similarly, North Carolina levied a prohibitive tax on newly imported slaves and then in 1794 banned the trade altogether. The trade remained open in Georgia in 1787, but in the wake of the Haitian Revolution, that state also banned it.

The Revolution brought freedom to slaves who joined the armies or escaped in the chaos of war. Thousands left South Carolina and Georgia when the British Army evacuated those states. Some of these people remained free, while others ended up being re-enslaved in the British Caribbean. At the end of the war, leaders in the Deep South fully expected to reopen the trade at some point, to replenish their slave holdings. However, in 1787, when the Constitutional Convention met in Philadelphia, no American state except Georgia had yet reopened the African trade. Nevertheless, with the expectation of reopening the international slave trade, the delegates from the Deep South jealously guarded their right to import more slaves. They succeeded with the provision in Article 1, Section 9 of the Constitution, which prevented Congress from ending the trade before 1808.

The Slave Trade and the Constitution

The final text of the slave trade provision was designed to disguise what the Convention had done. The clause read: "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, but a Tax or duty may be imposed on such Importation, not exceeding ten dollars for each Person."

It is important to understand that the clause did not require an end to the trade in 1808. Moreover, it reflected the assumption, held by almost everyone at the Convention, that the Deep South would grow faster than the rest of the nation, and that by 1808 the states that most wanted to continue the trade would have enough political power, and enough allies, to prevent an end to it. Ending the trade would require that a bill pass both houses of Congress and be signed by the president. That process would give the supporters of the trade three opportunities to stop such a bill.

The slave trade provision was a significant factor in the debates over ratification, but its impact was complicated. Opponents of the Constitution, in both the North and the South, roundly condemned the clause. On the other hand, supporters of the Constitution–even those who were ambivalent or hostile to slavery–praised it.

Northern supporters of the Constitution were at a rhetorical disadvantage in this debate, but they nevertheless had to engage the issue. They developed two tactics. The first, best put forth by James Wilson of Pennsylvania, was intellectually dishonest but politically shrewd. He argued that the slave trade clause would in fact allow for the end of slavery itself. In speeches he made the subtle shift from the "trade" to slavery, and since most of his listeners were not as legally sophisticated as Wilson, he was able to fudge the issue. Thus, Wilson told the Pennsylvania ratifying convention that after "the lapse of a few years... Congress will have power to exterminate slavery from within our borders."

Since Wilson attended all the debates over this clause, it is impossible to accept this statement as his understanding of the slave trade clause. More likely, he simply made this argument to win support for the Constitution. Supporters in Massachusetts and New Hampshire made similar arguments. In New Hampshire, a supporter of the Constitution also argued that the slave trade clause gave Congress the power to end slavery. A more sophisticated response to the trade was to note that, without the Constitution, the states could keep the trade open indefinitely because the Congress under the Articles of Confederation had no power to regulate commerce, but under the Constitution it would be possible, in just twenty years, to end the international slave trade. These arguments led northerners to believe that the Constitution required an end to the trade after 1808, when in fact it did not.

Upper South supporters of the Constitution, such as James Madison, also made the argument that a ban on the trade was impossible under the Articles, and thus the Constitution, even if imperfect, was still a good bargain. Deep South supporters, like General Charles Cotesworth Pinckney, simply bragged that they had won a great victory–as indeed they had–in protecting the trade for at least twenty years. In summing up the entire Constitution, Pinckney, who had been one of the ablest defenders of slavery at the Convention, proudly told the South Carolina House of Representatives: "In short, considering all circumstances, we have made the best terms for the security of this species of property it was in our power to make. We would have made better if we could; but on the whole, I do not think them bad."

Regulating the Trade

While Congress did not have the power to end the international slave trade, it did have the power to regulate it, and starting in 1794, it did just that.

In March, Congress prohibited the use of any U.S. port or shipyard for the purpose of fitting out or building any ship to be used for the introduction of slaves. The law also prohibited ships sailing from U.S. ports from trafficking in foreign countries. Ships sailing from the United States to Africa, even if of foreign registry, were required to "give bond with sufficient sureties, to the treasurer of the United States, that none of the natives of Africa, or any other foreign country or place, shall be taken on board... to be transported, or sold as slaves in any other foreign place, within nine months thereafter." Penalties under the law included fines ranging from $2,000 for outfitting a ship to $200 for an individual working on such a vessel. The act provided that the ships could be confiscated, and half of all fines given to any informants, thus providing an incentive for ship captains and mariners to monitor the activities of anyone they suspected of being involved in the illegal slave trade.

Until 1800 none of the states had reopened the African trade, which had been effectively closed since the Revolution. Before 1800 all introductions into the U.S. were thus illegal, even if the slaves were brought in by foreign ships. After 1800, however, Georgia and South Carolina reopened their international slave trade, and in the next eight years, these two states would introduce about 100,000 new slaves from Africa.

With the trade legally reopened in the Deep South, Congress sought to strengthen the prohibitions on American participation in it. In 1800 Congress amended the 1794 act by dramatically increasing fines for illegal American participation and by giving informants a right to the entire value of any ship condemned under the law. In addition to not allowing American ships to participate in the trade, the new law prohibited any American from having any interest in a ship involved in the trade. Thus, Americans could no longer invest in the transatlantic slave trade, even if carried on legally by non-U.S. ships.

If convicted, an American was subject to a fine that was double the value of his investment in the vessel and also double the value of any slaves in whom he had an interest. The 1800 amendment explicitly prohibited any American citizen or resident alien from voluntarily serving "on board any foreign ship or vessel . . . employed in the slave trade." It no longer mattered if the ship was U.S., or even if it left an American port. American sailors found on slavers were now subject to a $2,000 fine. The law authorized all "commissioned vessels of the United States, to seize and take any vessel employed" in the trade contrary to the law, with the crew receiving half the value of the ship when it was sold. This provided an enormous incentive for American ships to police the trade.

With the trade legal in some states and illegal in others, in 1803 Congress provided new fines for people who brought newly imported slaves into states that banned the international slave trade. The law applied to any "negro, mulatto, or other person of color" introduced as a slave, whether from Africa or the Caribbean. The language was apparently used to prevent people who might bring in Africans by claiming they were not slaves but servants or indentured servants, or claim that they were not actually African but Caribbean.

All three of these laws had been designed to limit American participation in the transatlantic slave trade, but they could not be used to stop the trade itself. Significantly, all of the laws passed before 1807 focused on ships, sailors, and investors. None of the laws had any provision for what should happen to slaves illegally brought into the United States. Indeed, while the 1794 law provided for the sale of a ship and its "tackle, furniture, apparel and other appurtenances" of a slaver, it did not mention what should happen to the slaves or any cargo on the ship. Presumably, they too would be sold for the benefit of the United States, the informant, or any other claimant under the three laws.

In his annual message to Congress in December 1806, Thomas Jefferson, who had long opposed the trade (but not slavery itself), reminded the nation that on January 1, 1808, the constitutional suspension of congressional power on this issue would finally expire. He took a moment in his address to "congratulate" his "fellow-citizens, on the approach of the period at which you may interpose your authority constitutionally to withdraw the citizens of the United States from all further participation in those violations of human rights which have been so long continued on the unoffending inhabitants of Africa, and which the morality, the reputation, and the best interests of our country have long been eager to proscribe." He noted that any law passed by Congress could not take effect until January 1, 1808, but he urged Congress to act quickly "to prevent by timely notice expeditions which can not be completed before that day." Congress readily complied with legislation to absolutely ban all importations of slaves after January 1, 1808.

The Act of 1807

The 1807 act was a comprehensive attempt to close the slave trade. By passing the law in March, Congress gave all slave traders nine months to close down their operations in the United States.

The ten sections of the 1807 act were designed to eliminate all American participation in the trade. Section 1 set the tone. After January 1, 1808, it would "not be lawful to import or bring into the United States or the territories thereof from any foreign kingdom, place, or country, any negro, mulatto, or person of colour, with intent to hold, sell, or dispose of such [person] ... as a slave, to be held to service or labour." The act provided an enormous penalty — up to $20,000 — for anyone building a ship for the trade or fitting out an existing ship to be used in the trade.

Penalties for participating in the trade varied. American citizens were subject to fines of up to $10,000 and jail terms of no less than five years and no more than ten years. Ships of any nation found in American ports or hovering off the American coast with Africans on them could be seized and forfeited, with the captain facing a $10,000 fine and up to four years in prison. Any American who purchased an illegally imported slave would lose that slave and be fined $8,000 for every one purchased. The law allowed the United States Navy to interdict ships involved in the illegal trade. It also required ships legally transporting slaves from one part of the nation to another (the domestic slave trade remained legal until 1865) to register their passengers with port authorities before commencing their voyage.

The law certainly had teeth to it. Fines under the statute were enormous, and the potential jail time was surely enough to discourage most slave smugglers. Moreover, for the Jefferson administration, which never much liked federal power, this act constituted a huge grant of power to the national government. Had Congress provided sufficient funding to enforce the law, it would surely have closed the trade. Funding would, however, be problematic until the Civil War.

There was one other problem with the 1808 law: the fate of the illegally introduced slaves. Logically, they should have been either freed in the United States or sent back to Africa. After all, one of the goals of the law was to end the importation of new slaves from Africa. But given the views of President Jefferson, and many of the leaders of his party, either option was impossible. Jefferson was deeply hostile to the presence of free blacks. In a letter to Edward Coles, shortly after he left office, he referred to them as "pests" in society. Thus, his administration had no interest in freeing Africans who were illegally introduced into the nation. Nor was the deeply parsimonious Jefferson likely to support spending any money on returning them to their homelands. They may have been illegally seized and illegally brought to America, but that did not mean they should be free.

Reflecting Jefferson's ideology of states' rights, his hatred of free blacks, and his refusal to spend money unless absolutely necessary, the law provided that slaves illegally found in the United States would be treated according to the law of the state in which they were found — or brought to. In practice, this meant they would become slaves in the United States, and that the states would profit by selling them.

Under the law the United States would make money from the sale of confiscated ships and the large fines imposed on anyone involved in the trade. People informing on those who violated the law, as well as the crews of naval ships that seized traders, would also share in the proceeds from the sale of the seized ships. Southern states would get money from the sale of illegally imported slaves, and southerners would have access to more slaves. Anticipating the logic of Chief Justice Roger B. Taney's decision in Dred Scott v. Sandford (1857), the Africans themselves would "have no rights," and remain slaves. In sum, the act of 1807 provided heavy penalties — great disincentives — for slave traders, but ignored the slaves themselves. They were treated like merchandise to be transferred from the smuggler to some owner who could get a clear title to them. The 1807 act sought to end the trade, but did nothing to undermine the legitimacy holding men and women in bondage. In that respect, it truly represented the ideology of the president who signed it into law.

The Act of 1818

In 1818 Congress passed an elaborate new act, technically an amendment to the 1807 law, but really more like a new statute. The new law tinkered with the penalties for various offenses. For example, the maximum fine for fitting out a ship was reduced to $5,000 and the jail time was reduced to no more than seven years. The reduction in penalties probably did not reflect any sense that the trade was less heinous. Rather, the original penalties were probably out of line with norms for punishments at the time. The most significant change in the law was the standard by which courts would judge those charged under the 1818 act. The new law shifted the burden of proof from the prosecution to the defendant. It required that defendant to "prove that the negro or mulatto, or person of colour, which he or they shall be charged with have being brought into the United States, or with purchasing ... was brought into the United States at least five years previous to the commencement of the prosecution." This section of the law created a statute of limitation of five years on the law banning the trade; but it also made prosecutions easier within those five years. Under this law, anyone in possession of an African-born slave might have to prove how he acquired him or her, demonstrating that person was in the United States at least five years before any prosecution. The "Africanness" of the individual would be prima facie evidence against an owner, to be rebutted only by contrary evidence the owner had to produce.

The Act of 1819

In 1819 Congress passed yet another act that dramatically changed the regulation of the trade. First, it authorized the president to send "armed vessels of the United States, to be employed to cruise on any of the coasts of the United States ... or the coast of Africa" to interdict slave traders. This was the beginning of what became known as the African Squadron, which patrolled the waters off the coast of Africa in an attempt to stop the slave trade at its source.

The law also provided that the slaves be returned to Africa, rather than being sold in the United States. This provision was directly tied to the creation of the African Squadron. The act authorized the president to appoint agents to receive rescued Africans and return them to the continent of their birth. The United States would use Liberia as a destination for Africans taken off intercepted ships. American ships could not seize slavers off the coast of Africa and immediately return the people on board to their point of origin. The law provided an economic incentive for sailors on these ships: a $25 bounty, to be shared by the crew of the interdicting vessel, for every individual rescued from traders. The act also provided a bounty of $50 per person to any informant whose information led to the recovery of illegally introduced Africans.

This act changed the direction of the suppression of the trade. The focus was now in part on the injustice of enslaving someone who deserved to be free. In part, the law now implicitly condemned American slavery itself. If it was wrong - unlawful - to enslave an African after 1819, why, someone might ask, was it not wrong to enslave an African before 1808? And if the original enslavement was morally wrong, then what was the basis of holding the descendants of that person in slavery? The act also took the United States out of the business of marketing slaves. Before 1819 confiscated slaves were sold under the laws of the states where they ended up. Naval crews and informants were in part compensated from the sale of these people. Now the taxpayers compensated naval crews and informants through bounties and the Africans went home. This was a dramatic change in American policy. For the first time in the nation's history, the United States was willing to spend money to help Africans regain their liberty.

The Act of 1820

The final statute to regulate the trade was passed in 1820, with the unlikely title "An Act to continue in force 'An act to protect the commerce of the United States, and to punish the crime of piracy,' and also to make further provisions for punishing the crime of piracy." The key element of the law were two sections declaring that any American citizen engaging in the African slave trade "shall be adjudged a pirate; and on conviction thereof before the circuit court of the United States for the district wherein he shall be brought or found, shall suffer death." The same language was applied to non-Americans found on board slavers owned or commissioned by Americans. This law was to be in force for only two years, but on January 3, 1823, Congress made it a permanent statute. This was a dramatic and important change in U.S. policy.

After 1820, participation in the African slave trade was to be considered the most heinous crime on the high seas — piracy — to be punished by death. Never before had the United States taken such a stand against any aspect of slavery. Enforcement would be a challenge. The Atlantic Ocean was vast; the African Squadron was always too small. Slavers captured in or near southern ports would be tried by juries sympathetic to slavery and not always hostile to the illegal slave trade. No slaver would be executed until the Lincoln administration actually enforced the law to its fullest. But the 1820 law was somewhat effective in curbing the trade. Few sailors were willing to risk their lives for the relatively paltry earnings on board a slaver. The high cost of failure — confiscation of a ship, large fines, jail time for the owner, and possibly death for the captain and crew — surely discouraged most would-be traders. Incentives for informing on Americans who bought illegally introduced Africans were high. With a bounty of $50 per slave, an informant could make $5,000 for tipping off authorities that one hundred Africans had been secretly and illegally landed. With a bounty of $25 a slave, the crews of the African Squadron had a strong incentive for acting "above and beyond" the call of duty. Even in cases where the slavers were not executed, ships were seized and forfeited, making the business very expensive and not very profitable.

To be sure, some slaves were smuggled into the United States after 1820 from both Africa and other places in the Western Hemisphere. But the risks were high and the numbers were relatively few. In an eight-year period, from 1800 until December 31, 1807, about 100,000 Africans were forcibly brought into the country. After 1820 it is unlikely that more than 10,000 were successfully landed in the United States. It may have been far fewer than that. As the internal slave trade replaced the African trade, hundreds of thousands of African-American slaves were uprooted and moved further south and further west. The cost of ending that trade would be much higher than ending the African trade. But the moral issue was set in 1819 and 1820 when the United States finally stated, in unequivocal terms, that enslaving people was a "wrong" and those who engaged in the African trade were no better than common pirates. And, like common pirates, they deserved to be hanged.

Paul Finkelman
President William McKinley Distinguished Professor of Law and Public Policy
Albany Law School


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