Officers with U.S. Immigration and Customs Enforcement (ICE) within the Department of Homeland Security (DHS) investigate violations of immigration laws and identify aliens who are removable from the United States. ICE officers exercise discretion to achieve its operational goals of removing any aliens subject to removal while prioritizing those who pose a threat to national security or public safety and safeguarding aliens' rights in the removal process. GAO was asked to examine how ICE ensures that discretion is used in the most fair, reasoned, and efficient manner possible. GAO reviewed (1) when and how ICE officers and attorneys exercise discretion and what internal controls ICE has designed to (2) guide decision making and (3) oversee and monitor officers' decisions. To conduct this work, GAO reviewed ICE manuals, memorandums, and removal data, interviewed ICE officials, and visited 21 of 75 ICE field offices.

The U.S. Government Accountability Office (GAO) is an independent agency that works for Congress. The GAO watches over Congress, and investigates how the federal government spends taxpayers dollars. The Comptroller General of the United States is the leader of the GAO, and is appointed to a 15-year term by the U.S. President. The GAO wants to support Congress, while at the same time doing right by the citizens of the United States. They audit, investigate, perform analyses, issue legal decisions and report anything that the government is doing. This is one of their reports.