...the Mail Isolation Control and Tracking program, in which Postal Service computers photograph the exterior of every piece of paper mail that is processed in the United States — about 160 billion pieces last year. It is not known how long the government saves the images.
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"In the past, mail covers were used when you had a reason to suspect someone of a crime,” said Mark D. Rasch, who started a computer crimes unit in the fraud section of the criminal division of the Justice Department and worked on several fraud cases using mail covers. “Now it seems to be, ‘Let’s record everyone’s mail so in the future we might go back and see who you were communicating with.’ Essentially you’ve added mail covers on millions of Americans.”
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“It’s a treasure trove of information,” said James J. Wedick, a former F.B.I. agent who spent 34 years at the agency and who said he used mail covers in a number of investigations, including one that led to the prosecution of several elected officials in California on corruption charges. “Looking at just the outside of letters and other mail, I can see who you bank with, who you communicate with — all kinds of useful information that gives investigators leads that they can then follow up on with a subpoena.”
But, he said: “It can be easily abused because it’s so easy to use and you don’t have to go through a judge to get the information. You just fill out a form.”
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Law enforcement officials need warrants to open the mail, although President George W. Bush asserted in a signing statement in 2007 that the federal government had the authority to open mail without warrants in emergencies or in foreign intelligence cases.
