Democratic members of the House Committee on Energy and Commerce have opened an investigation into the National Security Agency's clandestine wiretapping and surveillance program, and what role major telecom companies may have played in assisting the NSA.

Committee chair John Dingell (D-MI), Telecommunications Subcommittee chair Ed Markey (D-MA), and Oversight Subcommittee chair Bart Stupak (D-MI) sent letters to AT&T, Verizon, and Qwest, asking them to provide information on what customer information they may have provided the NSA, whether or not their efforts complied with the law, and if the government offered them immunity from lawsuits.

"We are eager to understand the process by which telecommunications carriers release customer records," reads the letter to AT&T CEO Randall Stephenson, "as well as the extent of reported efforts by government agencies to obtain information about customers, including their call records and data reflecting their Internet use."

Our government certainly has a responsibility to protect us from terrorism and threats to our national security, but that does not provide the government carte blanche to listen in on citizens calls, Stupak said in a statement.

I will be interested to learn what leverage, pressure and arguments the Administration used in persuading these telecommunications carriers to release customers proprietary information.

The committee also solicited comment on the government's increasing usage of measures such as "national security letters" to obtain personal and financial information from American citizens, even if they are not part of a criminal investigation.

Copies of the letters were sent to civil rights and privacy groups such as the American Civil Liberties Union and the Electronic Privacy Information Center. Republican members of the Commerce Committee did not sign the letters, but were provided copies.

The ongoing saga of the warrantless surveillance program has proven to be a perennial headache for the Bush administration and the telecom companies alleged to have assisted the NSA. Since the full scope of the program was revealed in 2005, Verizon flatly denied its participation in the program, Qwest claimed it declined to participate, and AT&T refused to comment, citing national security concerns.

The revelation of the program has led to a series of lawsuits against the NSA and the companies accused of assisting it, chiefly AT&T and Verizon, for violating the national Foreign Intelligence Surveillance Act (FISA), which governs the usage of wiretaps and surveillance for national security investigations, and requires compliance with the Fourth Amendment's injunctions against warrantless search and seizure.

Although the White House initially claimed the surveillance program did not fall under FISA authority and asking for warrants would take too long, former Attorney General Alberto Gonzalez abruptly reversed course in January 2007, and said the program would be placed under the overview of the Foreign Intelligence Surveillance Court (FISC), which administers FISA warrant requests.

The White House quickly pushed Congress to pass legislation legalizing the program, and Congress passed the "Protect America Act" in late July, which temporarily authorizes the program to continue for six months. After facing heavy criticism from civil liberties organizations over the Act's passage, Congressional Democrats have promised to reassess the program when the Act's temporary authority expires.

FISC then told the White House that it had to respond to a request from the ACLU to provide more information on the warrantless surveillance program.

Director of National Intelligence Mike McConnell admitted in an interview with the El Paso Times that major telecom carriers aided the NSA in the surveillance program, though he did not identify specific companies. McConnell said that the companies required immunity from lawsuits, or they would suffer severe financial hardship from damages if the cases were found in the plaintiffs' favor. McConnell has said he plans to push Congress to add blanket immunity from lawsuits for the telecom companies to any revisions of the Protect America Act.