The first woman to sit on the U.S. Supreme Court, Sandra Day O’Connor was known for a centrist pragmatism even as she often voted with the conservative bloc and waded into some of the most contentious issues during 25 years on the bench. The most politically provocative case of her tenure came in 2000, when the Supreme Court determined the presidential election. In a 5-4 split along ideological lines, with O’Connor joining the conservative majority, the court ruling resulted in George W. Bush’s victory over Al Gore. The divisive decision tainted the Justices with accusations of partisanship and tested Americans’ faith in their electoral system. —Tessa Berenson
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