Privacy advocates head to the White House on Thursday for what is likely to be their last chance to convince US President Barack Obama to decisively end the bulk collection of Americans’ communications data.

Representatives of the major privacy and civil libertarian organizations – including the American Civil Liberties Union, the Electronic Privacy Information Center (Epic) and the Open Technology Institute – arrive at the White House for a mid-afternoon meeting as expectations mount that Obama will propose changing the National Security Agency’s controversial database of all domestic phone call records.

But the civil liberties groups expressed concern that pushback from the NSA, its allies on Capitol Hill and those within the Obama administration will lead Obama to make cosmetic changes, rather than ending the mass surveillance, first reported by the Guardian thanks to leaks by whistleblower Edward Snowden.

“The White House must end the NSA bulk record collection activities,” said Alan Butler, a lawyer with Epic, voicing the bottom line of the civil liberties coalition.

There are gradations, however, in what counts as “ending” the bulk surveillance. Both civil libertarians and the NSA are jockeying for their definition to prevail with the president.

Obama is holding a flurry of meetings with surveillance stakeholders this week before announcing which surveillance programs he will end, modify and reaffirm. On Wednesday he met with his leaders of the intelligence agencies, including NSA director Keith Alexander, director of national intelligence James Clapper, FBI director James Comey and CIA director John Brennan, all of whom have deep interests in the future contours of US surveillance efforts. Obama also met Wednesday with his Privacy and Civil Liberties Oversight Board, which plans to issue a report on the NSA’s phone metadata collection as early as late January.

On Thursday morning, Obama will meet with key legislators overseeing the surveillance efforts, including skeptics like Democratic Senator Ron Wyden of Oregon and Republican Representative James Sensenbrenner of Wisconsin. On Friday, White House staff members are expected to meet with technology firms, which the White House did not identify, to hear their concerns as well.

Obama will not attend the Thursday afternoon meeting with the privacy advocates. Their liaison to the president will be White House counsel Kathryn Ruemmler.

On the surface, it appears a consensus is taking shape to revamp the bulk collection of domestic phone data, spurred by a recommendation to that effect in December by a review group Obama empanelled to advise him on surveillance.

That advisory group proposed having a third party, such as the phone companies, retain the phone records on behalf of the NSA – an initiative that civil liberties groups consider both laden with promise and fraught with peril.

For months, the NSA and its allies have signalled they can accept giving up their role as custodians of the phone records database, provided that the database be as comprehensive as it currently is, and that the NSA can search the trove under conditions comparable to the “reasonable articulable suspicion” of connection to terrorism standard that pertains currently.

“I would love to give this hornet’s nest to someone else, to say ‘You get stung by this.’ But don’t drop it, because that’s our country, and if you do drop it, the chance of that a terrorist attack gets through increases,” Alexander told a Bloomberg forum in October.

Keith Alexander, second left, with deputy Chris Inglis, and director of national intelligence James Clapper. Photograph: Susan Walsh/AP Photograph: Susan Walsh/AP

But the privacy groups meeting with the White House counsel’s office consider that to be a repackaging of bulk metadata surveillance.

“Maintaining the same standard of access to data, whether by the [phone] companies or a third party, would not constitute an end to the program, it would just be bulk collection by proxy,” said Kevin Bankston, the policy director of the Open Technology Institute, who plans on attending the meeting.

The privacy groups are not opposed to allowing the government access to the records, but they want a higher legal standard for allowing intelligence or law enforcement agencies to access any database of Americans’ phone records, pursuant to a court order ahead of any search except in extreme cases.

Currently the NSA does not have to obtain a court order for any individual search; every 90 days the secret surveillance panel known as the Fisa Court issues omnibus authorizations for bulk collection and analysis based on “reasonable articulable suspicion” of terrorist connections.

“Reasonable articulable suspicion, we still think that’s too vague,” said Michelle Richardson, the ACLU’s surveillance lobbyist.

The groups support the USA Freedom Act, a bill in Congress sponsored by Sensenbrenner and Vermont Democrat Patrick Leahy, which would force the government to convince a court that the “tangible things sought … are relevant and material to an authorized investigation” and pertain to either a foreign power; someone working for one; or the activities of someone or their associates connected to an authorized investigation.

But perhaps the strongest argument the civil liberties groups feel they need to articulate at the White House concerns the scope of any post-NSA phone records database. The phone companies, on average, store customer data for 18 months before purging it; the NSA stores it for five years, and has said it can live with three-year storage. In a footnote, Obama’s review group said two years maximum data storage was reasonable.

“I think it’s fair to say that the privacy community and the telecoms and internet industry, as well a many key leaders in Congress have made it clear that mandatory data retention is a non-starter and that has not changed,” Bankston said.

Recreating that database outside of the NSA – the “hornet’s nest,” in Alexander’s words – poses a dilemma for Obama. The phone companies vary not only on how long they store customer data, but also in the file formats, which the NSA has warned complicates a data set whose value depends on its comprehensiveness and easy searchability.

Yet the phone companies, who have conspicuously not publicly waded into the post-Snowden surveillance fracas, have indicated that they do not want to be the custodians of an expanded data trove, for reasons of both expanded legal liabilities and additional cost. The NSA and civil liberties groups have found common ground in arguing that a privately held phone records trove would be difficult to keep secure from attempts at hostile data exfiltration.

Some privacy advocates feel that the surveillance debate has entered a political vacuum. The USA Freedom Act has yet to clear any committee. Privacy groups and the NSA can each cite a December victory in the federal courts to bolster their arguments for the appropriate scope of domestic surveillance.

Lawmakers, particularly Democrats, are waiting to hear Obama’s surveillance proposals before making any definitive proclamations about what the president has described as a “balance” between liberty and security. Capitol Hill sources indicated Tuesday that the confusion was likely to get worse before it gets better, particularly if Obama ends up proposing a new custodian of phone records data, which will have to be built from scratch.

“The political landscape right now I would call absolute chaos,” said the ACLU’s Richardson. “We’ve not given up hope. But it’s very confusing right now.”