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Women of the Year
Fred Schilling––ZUMA

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

This article is part of 100 Women of the Year, TIME’s list of the most influential women of the past century. Read more about the project, explore the 100 covers and sign up for our Inside TIME newsletter for more.

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