A prominent senator unveiled legislation Tuesday that would end the National Security Agency's bulk collection of all telephone metadata—a package that still provides the nation's spooks limited access to the data of every phone call made to and from the US. And the probable-cause standard under the Fourth Amendment is not present.

Conceding the realpolitik, civil rights groups and others are backing the proposal from Patrick Leahy, the Democratic chairman of the Senate Judiciary Committee, even though the NSA may acquire the data absent constitutional protections.

The American Civil Liberties Union supported the legislation—called the USA Freedom Act—while admitting that it's "not perfect." The ACLU said:

The Senate bill is an improvement over the version passed by the House, but problems remain. It is important that the public understand that there is much more work to be done to narrow the government’s overbroad surveillance authorities to bring them in line with our Constitution and values. This is a marathon, not a sprint, and we have miles left to go

The New York Times even weighed in, saying that the measure "represents a breakthrough in the struggle against the growth of government surveillance power."

All the celebrations concerning the Leahy measure were in response to the bill's perceived impact of countering greater spying powers for the NSA.

The Center for Democracy & Technology, which opposed the House bill, supported the Leahy measure, saying Tuesday that it was a "significant step forward in protecting Americans from unnecessary and intrusive NSA surveillance."

A better choice—if you like privacy

An NSA whistleblower disclosed more than a year ago that the secret Foreign Intelligence Surveillance Court was ordering the nation's telcos to provide the NSA with all metadata associated with telephone calls made within the US or those going in and out. The NSA was given virtually carte blanche access to the data, although it promised it wouldn't sift through it unless it had "reasonable, articulable suspicion" against a terrorism target. That target could include an entire zip code.

The phone metadata includes the numbers of both callers, the duration and time of a call, international mobile subscriber identity numbers of mobile callers, and calling card numbers.

Under Leahy's bill, the metadata would stay with the telephone carriers. And the NSA wouldn't have willy-nilly access to it. Instead, the NSA would have to ask this secret court to demand that carriers turn over data associated with a "specific selection term" such as a phone number or name, and the government would have to explain how it believes that the selector is associated with terrorism. Again, standards under the Fourth Amendment are not required.

“This is an historic opportunity, and I am grateful that the bill has the support of the administration, a wide range of privacy and civil liberties groups, and the technology industry," Leahy said during a Judiciary Committee hearing Tuesday.

The Reform Government Surveillance Coalition, which includes Google, Microsoft, and Yahoo as members, seemed elated by the measure.

“This bill will help restore trust in the Internet by ending the government’s bulk Internet metadata collection and increasing transparency around US surveillance practices,” the organization said.

The Leahy package is clearly a better choice for privacy enthusiasts than the House bill—also called the USA Freedom Act—approved in May in a 303 to 121 vote. Although that bill did remove the telephone metadata from the NSA's hands, it granted the administration broad spying powers.

Under the House bill, a database search inquiry is allowed if it is "a discrete term, such as a term specifically identifying a person, entity, account, address, or device." Civil rights groups objected to the measure because the bill's language was so vague that it allowed the NSA to ensnare the metadata of innocent people in violation of their constitutional rights.