Chilean heiress Blanca Erraazuriz gunned down her ex-husband John de Saulles in front of several witnesses on August 3, 1917. As the former football star lay bleeding on the porch of his Long Island home, she handed her empty gun to the sheriff. "I hope he dies," she calmly confessed. The murder shocked the nation, bumping World War I from the newspaper headlines. Her trial whipped up a frenzy of public sympathy for a young mother driven to desperation by a cheating husband. When a jury of middle-aged men declared her not guilty, she strolled out of court a free woman and regained full...