President James A. Garfield succumbed to bullet wounds sustained by an assassin. Vice President Chester A. Arthur's succession to the presidency removed him from the Senate at a time when his tie-breaking vote was of special importance. For the first time in its history, the body stood equally divided between Republicans and Democrats. Two independent members, William Mahone of Virginia and David Davis of Illinois helped shape institutional decisions. When Arthur took the president's oath, the parties in the Senate declared a truce. For the balance of that Congress, Republicans controlled the committees and Democrats managed the patronage.
The Senate approved twelve amendments to the Constitution. Ten of these amendments, which were subsequently ratified, became known as the Bill of Rights. Three-fourths of the state legislatures ratified Articles 3 through 12 on December 15, 1791. The amendments defined the rights of individuals and delivered on promises made during the state ratification debates over the Constitution. An eleventh amendment, regarding compensation of members, waited more than two centuries before being ratified as the Twenty-seventh Amendment on May 7, 1992. The first amendment, which related to the number of constituents for each member in the House of Representatives, was never ratified.