Three-fifths compromise

The Three-Fifths Compromise was a compromise reached between delegates from southern states and those from northern states during the 1787 United States Constitutional Convention. The debate was over whether, and if so, how, slaves would be counted when determining a state's total population for legislative representation and taxing purposes. The issue was important, as this population number would then be used to determine the number of seats that the state would have in the United States House of Representatives for the next ten years. The effect was to give the southern states a third more seats in Congress and a third more electoral votes than if slaves had been ignored, but fewer than if slaves and free persons had been counted equally, allowing the slaveholder interests to largely dominate the government of the United States until 1861. The compromise was proposed by delegates James Wilson and Roger Sherman.

The Convention had unanimously accepted the principle that representation in the House of Representatives would be in proportion to the relative state populations. However, since slaves could not vote, white leaders in slave states would thus have the benefit of increased representation in the House and the Electoral College. Delegates opposed to slavery proposed that only free inhabitants of each state be counted for apportionment purposes, while delegates supportive of slavery, on the other hand, opposed the proposal, wanting slaves to count in their actual numbers. The compromise that was finally agreed upon—of counting "all other persons" as only three-fifths of their actual numbers—reduced the representation of the slave states relative to the original proposals, but improved it over the Northern position. An inducement for slave states to accept the Compromise was its tie to taxation in the same ratio, so that the burden of taxation on the slave states was also reduced.

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