31 U.S.C. § 5311

It is the purpose of this subchapter (except section 5315) to— (1) require certain reports or records that are highly useful in— (A) criminal, tax, or regulatory investigations, risk assessments, or proceedings; or (B) intelligence or counterintelligence activities, including analysis, to protect against terrorism; (2) prevent the laundering of money and the financing of terrorism through the establishment by financial institutions of reasonably designed risk-based programs to combat money laundering and the financing of terrorism; (3) facilitate the tracking of money that has been sourced through criminal activity or is intended to promote criminal or terrorist activity; (4) assess the money laundering, terrorism finance, tax evasion, and fraud risks to financial institutions, products, or services to— (A) protect the financial system of the United States from criminal abuse; and (B) safeguard the national security of the United States; and (5) establish appropriate frameworks for information sharing among financial institutions, their agents and service providers, their regulatory authorities, associations of financial institutions, the Department of the Treasury, and law enforcement authorities to identify, stop, and apprehend money launderers and those who finance terrorists.