Storified by AJAMStream· Tue, Dec 10 2013 15:43:39

Privacysos

Crockford's chart alludes to reports that AT&T had provided the Drug Enforcement Administration with call records dating back 26 years, contradicting the company's claim to Sen. Markey that they only store CDRs for 5 years.

The second chart details the legal mechanisms each company requires for the release of each type of user data to law enforcement. The mechanisms employed range from subpoenas, which require no judicial involvement or probable cause, to warrants and wiretap orders, which require both.

Privacysos





The letters also reveal the major cell phone providers receive significant financial reimbursements from law enforcement and employ large numbers of staff to process the growing government requests. AT&T alone received over $10 million in compensation from federal, state and local law enforcement agencies. AT&T also wrote that they employ more than 100 full-time staff to operate a 24/7 service center for processing law enforcement requests.





What do you think? Does information in these letters affect your opinion of your cell phone provider?

U.S. Cellular's letter to Sen. Markey includes a numerical breakdown of each type of request they received from law enforcement. The company received 10,801 subpoenas in 2012, compared with 702 warrants. Cellular customers who have their data subpoenaed by law enforcement are usually not informed . If a customer were to find out somehow that their records had been subpoenaed, the " third party doctrine " would in most cases prevent the subpoena from being rejected, as it states that Americans have no right to privacy when they hand over information to a third party like a cell phone provider.