From the IRS website, Bank Secrecy Act History and Law:
4.26.5.2 (01-01-2003)
History of the Bank Secrecy Act
1.
On October 26, 1970, in response to increasing reports of people bringing bags full of currency of doubtful origin into banks for deposit, Congress passed the Currency and Foreign Transactions Reporting Act, Public Law 91-508. This law is often cited as the Bank Secrecy Act (BSA) because Part I, codified in Title 12 of the United States Code (U.S.C.) requires in part that banks not keep secret certain internal changes. Part II of the law, sometimes cited as the Currency and Foreign Transactions Reporting Act, is codified now at 31 U.S.C., Money and Finance, Chapter 53, Monetary Transactions, Part II, Records and Reports on Monetary Instruments Transactions. Since the law appears in Title 31, the Anti-Money Laundering (AML) compliance program based on it is often called the Title 31 program to distinguish it from Title 26, Internal Revenue Code (IRC) Section 6050I, law side of the AML program.
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