What is the nations largest law-enforcement agency?

The largest law enforcement agency in the United States is the Federal Bureau of Investigation (FBI). Established in 1908, the FBI is tasked with investigating and enforcing Federal Laws, tackling a wide range of issues including terrorism, cybercrime, organized crime, and public corruption. It operates under the Department of Justice and has a significant presence across the country and internationally. The agency employs thousands of agents and support staff, making it a critical component of national security and law enforcement.