America's runaway inequality has an engine: our unjust tax system. Even as they became fabulously wealthy, the ultra-rich have seen their taxes collapse to levels last seen in the 1920s. Meanwhile, working-class Americans have been asked to pay more. The Triumph of Injustice presents a forensic investigation into this dramatic transformation, written by two economists who revolutionized the study of inequality. Eschewing anecdotes and case studies, Emmanuel Saez and Gabriel Zucman offer a comprehensive view of America's tax system, based on new statistics covering all taxes paid at all levels of government. Their conclusion? For the first time in more than a century, billionaires now pay lower tax rates than their secretaries. Blending history and cutting-edge economic analysis, and writing in lively and jargon-free prose, Saez and Zucman dissect the deliberate choices (and sins of indecision) that have brought us to today: the gradual exemption of capital owners; the surge of a new tax avoidance industry; and the spiral of tax competition among nations. With clarity and concision, they explain how America turned away from the most progressive tax system in history to embrace policies that only serve to compound the wealth of a few.