FinCEN -Financial Crimes Enforcement Network
Overall authority for enforcement and compliance, including coordination and direction of procedures and activities of all other agencies exercising delegated authority, has been delegated by the Secretary of the Treasury to the Assistant Secretary of the Treasury (Enforcement). FinCEN has been designated by the Assistant Secretary of the Treasury (Enforcement) to administer the Bank Secrecy Act.
See 31 CFR 103.56(a)