The National Institute of Justice (NIJ) is the research, development, and evaluation agency of the United States Department of Justice (DOJ).

The United States Department of Justice (DOJ), also known as the Justice Department, is a federal executive department of the United States government tasked with the enforcement of federal law and administration of justice in the United States. It is equivalent to the justice or interior ministries of other countries. The department is headed by the U.S. attorney general, who reports directly to the president of the United States and is a member of the president's Cabinet. The current attorney general is Merrick Garland, who has served since March 2021.