The Supreme Court closed a 6-year-old chapter Tuesday in the Electronic Frontier Foundation's bid to hold the nation's telecoms liable for allegedly providing the National Security Agency with backdoors to eavesdrop, without warrants, on Americans' electronic communications in violation of federal law.

The justices, without comment, declined to review a lower court's December decision (.pdf) dismissing the EFF's lawsuit challenging the NSA's warrantless eavesdropping program. At the center of the dispute was 2008 congressional legislation retroactively immunizing the telcos from being sued for cooperating with the government in a program President George W. Bush adopted shortly after the September 2001 terror attacks.

After Bush signed the legislation and invoked its authority in 2008, a San Francisco federal judge tossed the case, and the EFF appealed. Among other things, the EFF claimed the legislation, which granted the president the discretion to invoke immunity, was an illegal abuse of power.

The New York Times first exposed the NSA’s warrantless wiretapping of international phone calls to and from Americans in 2005. A former AT&T technician named Mark Klein later produced internal company documents suggesting that the NSA was surveilling internet backbone traffic from a secret room at an AT&T switching center in San Francisco, and similar facilities around the country. Klein’s evidence formed the basis of the now-dismissed suit, Hepting v. AT&T.

Cindy Cohn, the EFF's legal director, said the group was "disappointed" with the outcome because "it lets the telecommunication companies off the hook for betraying their customers' trust."

The Bush administration, and now the President Barack Obama administration, have neither admitted nor denied the spying allegations — though Bush did admit that the government warrantlessly listened in on some Americans' overseas phone calls, which he said was legal.

But as to widespread internet and phone dragnet surveillance of Americans, both administrations have declared the issue a state secret — one that would undermine national security if exposed.

After six years of legal jockeying, the merits of the allegations have never been weighed in the litigation. But some portions of them still might.

That's because litigation on the surveillance program continues. After U.S. District Judge Vaughn Walker tossed the case against the telcos, the EFF sued the government instead. Walker dismissed that case, too, ruling that it amounted to a "general grievance" from the public and not an actionable claim. But a federal appeals court reversed, and sent it down to a trial judge in December.

Judge Margaret McKeown, of the 9th U.S. Circuit Court of Appeals, ruled that the EFF’s claims "are not abstract, generalized grievances and instead meet the constitutional standing requirement of concrete injury. Although there has been considerable debate and legislative activity surrounding the surveillance program, the claims do not raise a political question nor are they inappropriate for judicial resolution."

A hearing on that case is scheduled next month in San Francisco federal court.

The Obama administration is again seeking it to be tossed, claiming it threatens to expose state secrets and would be an affront to national security. When the state secrets doctrine is invoked, judges routinely dismiss cases amid fears of exposing national security secrets.

On Monday, President Obama said that in the presidential contest with Republican challenger Mitt Romney: "We haven’t talked about what's at stake with respect to civil liberties." One might say that hasn't been heard in the courts, either, under Obama's tenure.