Reviewed by Richard E. Dixon
The 3/5ths clause was adopted by the Second Continental Congress in the Articles of Confederation as means of counting the slaves for two purposes, establishing the number of representatives in Congress by population, and establishing the ratio for direct taxation of the states.
At that time there was no "federal" or central taxing authority. Taxation of the states could not be enforced by the Continental Congress. The slave holding states wanted slaves counted as part of the population to increase the number of representatives and the northern states wanted them counted for purpose of taxation. This resulted in a compromise to count them as 3/5ths of a person. The clause was later included in the U. S. Constitution (Art I, Sec 2(3)), as the means to determine the number of representatives in the new House of Representatives. It never became important as a means of taxation as revenue was raised by indirect taxation.
Garry Wills does not claim that Jefferson exerted any personal influence in the 3/5th compromise although he was a member of the Second Continental Congress, but not of the Constitutional convention that perpetuated it. Then, in the election of 1800, Aaron Burr and Thomas Jefferson tied in the number of electoral votes, which were determined by the number of Representatives and Senators.
Wills makes the point that but for the slave population increasing the number of representatives for the south, Jefferson would have lost to John Adams in the Electoral College and the decision on the presidency would never have gone to the House of Representatives; hence, the “Negro President.” Wills, however, then goes on to make the argument that Jefferson supported slavery in the Louisiana Territory to guarantee its division into future slave states and continued dominance in the House of Representatives by the slave states. The argument has been long made that the Jefferson-Madison-Monroe presidencies protected slavery (Slavery and Jeffersonian Virginia, by Robert McColley, University of Illinois Press, 1964; which, interestingly, Wills does not cite). But Wills claims that Jefferson opposed the Missouri Compromise, not because it permitted slavery in Missouri, but because it banned slavery in the remaining Louisiana Territory (above Missouri's southern boundary). There are no cites to support this and Wills drifts off to extol the anti-slavery efforts of Timothy Pickering and John Quincy Adams. Wills does not quote Jefferson's comment that the vote on the Missouri Compromise was the "death knell of the union."