There has been a lot of discussion about the legality of the NSA's telephone data collection and analysis program, most of it not very illuminating. I haven't had an opportunity to form an opinion, and I'm not an expert in telecommunications law. In my quick review of what seems to be the relevant law, I've encountered several puzzling provisions. But one section I haven't yet seen cited, which seems relevant, is Title 18, Chapter 121, Section 2709 of the U.S. Code. It specifically allows the government to obtain telephone records for purposes of investigating terrorist threats. Here is Sec. 2709 in its entirety; I have highlighted some of the pertinent language:
§ 2709. Counterintelligence access to telephone toll and transactional records
(a) Duty to provide.--A wire or electronic communication service provider shall comply with a request for subscriber information and toll billing records information, or electronic communication transactional records in its custody or possession made by the Director of the Federal Bureau of Investigation under subsection (b) of this section.
(b) Required certification.--The Director of the Federal Bureau of Investigation, or his designee in a position not lower than Deputy Assistant Director at Bureau headquarters or a Special Agent in Charge in a Bureau field office designated by the Director, may--
(1) request the name, address, length of service, and local and long distance toll billing records of a person or entity if the Director (or his designee) certifies in writing to the wire or electronic communication service provider to which the request is made that the name, address, length of service, and toll billing records sought...
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UPDATE: Maybe I'm the only one who didn't already know this, but I was astonished to learn that there is no expectation of privacy in telephone records at all. Section 2702(c) sets out the circumstances in which a telecom provider can disclose phone records, not including the contents of communications. So this would cover the call information at issue in this program. 2702(c)(6) says that such phone records may be freely disclosed, at the company's discretion:
(6) to any person other than a governmental entity.