A creepy issue is bubbling up in Congress involving the dramatic uptick in the number of requests to cellular carriers from law enforcement for people’s cell phone records.

The number, announced earlier this month by Rep. Ed Markey (D-Massachusetts), is incredible: In the last year federal, state, and local law enforcement agencies have made 1.3 million demands for user cell phone data such as text messages, caller locations, and wiretaps; and that estimate is certainly low, albeit a huge increase compared with previous years.

This week Markey and three other Democrats sent a letter (PDF) to several House Republicans asking for a hearing to look at whether consumer privacy is being sufficiently protected by law enforcement and wireless carriers.

Privacy advocacy groups such as the Electronic Frontier Foundation say it isn’t, considering that much of this cell phone surveillance is done without a warrant.

But even more troubling is the fact that cellular carriers actually make a lot of money handing over their user’s private information.

In the July 16 letter the authors wrote, “The carriers’ responses also show that they are being compensated for providing this information to law enforcement agencies. Verizon charges to law enforcement ranged from $50 to retrieve up to five days of stored text message content to $1825 for multiple wiretap switches. AT&T received more than $8.2 million in 2011 for ‘collecting and submitting customer phone usage information to law enforcement.’”

In case you think you don’t have anything to hide, keep in mind the kinds of things your cell phone data can bring to light.

According to the EFF, cell phone location information -- which it says is protected by the Fourth Amendment prohibition against search and seizure -- “can reveal the most intimate details of one’s life,” including things like if a person regularly attends church, drinks heavily, exercises frequently, or cheats on a spouse.

The EFF also notes that Markey “and other members of Congress are working on legislation that would draw a clearer line on how the police can get access to such data,” although the advocacy group points out the Obama administration has previously argued that it’s “burdensome” to require law enforcement to get a warrant for personal information such as cell phone data.

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