Immigration law enforcement and adjudication were consolidated in the Immigration and Naturalization Service (INS) inside DOJ before 2003, but the Homeland Security Act of 2002 split INS’s functions into multiple agencies inside the new DHS while leaving the immigration courts in DOJ. [1][2]

Pre‑DHS structure (before 2003)

Immigration courts and EOIR

Homeland Security Act and breakup of INS

Post‑DHS enforcement structure

Continuity and change in proceedings

• Sources