SWIFT surveillance of international financial transactions. After 9/11, the US Treasury Department began the Terrorist FinanceTracking Program which served the international secure messaging system known as SWIFT (Society for Worldwide Interbank Financial Telecommunication) based in Belgium with broad subpoenas which resulted in the network turning over large parts of its database involving millions of records to US authorities.
Essentially, the US government was allowed to peek in on most of the international wire transfers between banks in the world. As long as all parties are foreign, US law does not have much to say about this, but many transactions involved Americans. This brings up 4th Amendment considerations which expressly forbid “unreasonable searches and seizures” and demand a warrant that is both specific and based on “probable cause”. Hoovering up for data mining purposes millions of bank records of ordinary Americans sending money abroad violates all aspects of this Constitutional protection. The program came to light on June 23, 2006 in articles in major US papers. Subsequently, there were announcements that the program had been modified but it was not clear how. The real question is how many of these post-9/11 “emergency” programs of dubious legality are still out there running years later.