In a world where decisions are increasingly scrutinized to ensure fairness across legally protected groups, it is critical to apply such scrutiny in a manner that is consistent with the law. This dissertation attempts to reconcile the legal definition and empirical measurement of disparate impact, one of two forms of discrimination recognized by United States anti-discrimination law. The first chapter of the dissertation lays the groundwork for the empirical measurement of disparate impact in decision-making scenarios where individual-level qualification can been estimated. The chapter details the application of this framework to a novel dataset of 1.5 million police stops recorded by large law enforcement agencies in California, and, for the majority of agencies, provides evidence of potential disparate impacts of police searches on Hispanic individuals and Black individuals. The second chapter applies the same disparate impact framework to the more complex setting of federal pretrial detention, which involves multiple decision makers and multiple decisions. We find evidence of disparate impact on Hispanic defendants, tracing our results, in part, to a statutory mandate that more often applies to Hispanic defendants and Black defendants. The third and final chapter examines disparate impact in selective college admissions, a decision making setting in which there does not exist an agreed-upon definition of individual-level qualification. I conclude the dissertation by discussing the limits of risk-based approaches to quantifying disparate impact. My hope is that, by aligning the legal interpretation of disparate impact and its empirical measurement with a coherent framework, and illustrating when and how this framework can be applied, this dissertation will serve as a source of insight for future researchers and policymakers seeking to make more equitable decisions. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]