Amendment IV, Where Art Thou?

The Obama administration is drawing up plans to give all U.S. spy agencies full access to a massive database that contains financial data on American citizens and others who bank in the country, according to a Treasury Department document seen by Reuters.
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Financial institutions that operate in the United States are required by law to file reports of "suspicious customer activity," such as large money transfers or unusually structured bank accounts, to Treasury's Financial Crimes Enforcement Network (FinCEN).

The Federal Bureau of Investigation already has full access to the database. However, intelligence agencies, such as the Central Intelligence Agency and the National Security Agency, currently have to make case-by-case requests for information to FinCEN.

The Treasury plan would give spy agencies the ability to analyze more raw financial data than they have ever had before, helping them look for patterns that could reveal attack plots or criminal schemes.

The planning document, dated March 4, shows that the proposal is still in its early stages of development, and it is not known when implementation might begin.

Hat tip to Bryan Preston.

Apparently, some legal experts are saying that this is legal, in part, to a combination of Bank Secrecy Act and the USA PATRIOT Act. I'm not buying it:

Fourth Amendment to the United States Constitution

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.