Pinckney's concern that the new United States could not negotiate vigorously
over commercial matters with foreign powers made him a supporter of plans
to strengthen the Articles of Confederation. Pinckney helped draft plans
to revise the Articles (by giving the Confederation government power to
regulate commerce, raise revenues, and adjudicate court cases concerning
national issues), but when the Constitutional Convention was called, Pinckney
went as one of the strongest supporters of creating a more powerful national
government.. Pinckney submitted an extended plan for revisions of the Articles
(similar to Madison's suggestions, but whereas Madison's became the "Virginia
Resolutions" and the starting point for debate at Philadelphia, Pinckney's
plan was not debated on the floor of the convention and no text of the
plan now exists). Pinckney spoke frequently during the Convention. He favored
a "high-toned" or aristocratic government (such as existed in South Carolina)
as well as one in which the central government had power to control the
separate states (a position he shared with Madison). At the same time,
he was a vigorous defender of slavery, and believed that slaves should
be fully counted in the basis for representation in any legislative bodies
in which the number of delegates assigned a state depended on population.
In South Carolina, Pinckney championed ratification.
In the new republic, Pinckney served four times as governor of South
Carolina, and as a member of the United States House of Representatives.
Initially a supporter of the Washington administration, he moved toward
the Jeffersonian opposition. In 1820, during the debate over the admission
of Missouri as a slave state, Pinckney again gained national attention
as one of two members of Congress who had been at the Constitutional Convention
and who could apparently speak authoritatively about the original intent
of the framers in regard to slavery.
Sources: there is no full-length biography of Pinckney. The best introduction to his role in the convention is chapter 7 (pp. 64-74) of Christopher Collier and James Lincoln Collier, The Constitutional Convention of 1787 (N.Y., 1986).