Several members of the Gang of Eight, a group of US Congress members who are sworn to secrecy on intelligence matters, want to know more about what Donald Trump discussed with Vladimir Putin. One way to find out: Summoning Trump’s interpreter to testify to the group.

Marina Gross, a veteran State Department interpreter, was the only other American in the room when Trump and Putin met for the two-hour private meeting in Helsinki on July 16. What exactly was discussed and agreed has become a critical issue, because the Russian government and the Trump administration appear to have different recollections of the meeting: Russia’s ambassador to the US said the two leaders made “important verbal agreements” on Syria and arms control, while the State Department and White House initially said no concrete deals were made.

Reversing course, White House press secretary Sarah Sanders tweeted this afternoon that the US had agreed to a “working level dialogue” between with Russia’s security council, and that Putin would visit the US this fall.

Democrats on the House Intelligence Committee have already made a request to subpoena Gross, but their proposal was voted down by Republicans. At the Senate Foreign Relations Committee, Republicans have also dismissed calls for her to testify, saying it would set a precedent that the US president couldn’t have any private conversations with foreign leaders.

Now, Democratic members of the Gang of Eight are floating the idea of having Gross testify privately before them. Senator Mark Warner, a Virginia Democrat, “wants clarity on what happened in the private session,” his spokeswoman told Quartz. This could include “testimony from the interpreter, copies of her notes, or a briefing” from administration officials.

Gross’s appearance in front of the Gang of Eight would technically eliminate the privacy problem, because the members are sworn to secrecy (PDF, page 4). While the president is required to keep Congress’s intelligence committees appraised of activities that affect national security, in “extraordinary circumstances” requiring extreme secrecy, he can inform the Gang of Eight instead. US law states:

If the President determines that it is essential to limit access to the finding to meet extraordinary circumstances affecting vital interests of the United States, the finding may be reported to the chairmen and ranking minority members of the congressional intelligence committees, the Speaker and minority leader of the House of Representatives, the majority and minority leaders of the Senate, and such other member or members of the congressional leadership as may be included by the President.

The Gang of Eight is evenly split between Republicans and Democrats, and includes the intelligence committee chairs from both parties, and leaders from both sides of Congress. Its members are:

Mitch McConnell, Senate majority leader

Chuck Schumer, Senate minority leader

Paul Ryan, Speaker of the House

Nancy Pelosi, House minority leader

Devin Nunes, the House Intelligence Committee chair

Adam Schiff, the Democratic leader on the House Intelligence Committee

Richard Burr, chair of the Senate Intelligence Committee

Mark Warner, the Democratic leader on the Senate Intelligence Commit

Democrats hold more sway on the Gang of Eight than they do in Congress as a whole right now, because unlike Congressional committees’, its agenda is not dictated by the chair. (In every Congressional committee, that’s currently a Republican.) Schiff, Schumer, and Pelosi have all called publicly for more information about the Trump and Putin meeting. Republican members of the gang have been critical of the meeting in general: Ryan said the president “must appreciate that Russia is not our ally,” and Burr said Trump should realize that Putin is lying about Russian meddling in the US 2016 election.

The mixture of House and Senate members could make the Gang of Eight’s approach more rigorous as well.

The House’s investigation into Russian meddling ended in a bipartisan stalemate in May. The Republican-led House Intelligence Committee declared there was no collusion between Russia and Trump, while Democrats on the committee said the issue had not been sufficiently investigated. The Senate’s approach has been much more thorough and bipartisan. The Senate Intelligence Committee, headed by Burr, said in May it concurs with a January 2017 intelligence report that Russia meddled in the presidential election in order to assist Trump.

The White House and State Department didn’t immediately respond to questions about the possibility of Gross testifying in front of the Gang of Eight, or supplying any notes to the group. Press Secretary Sarah Sanders said yesterday that she wasn’t aware of any recording of the meeting between Trump and Putin, and referred further questions to the State Department. In response to questions, the State Department reiterated spokeswoman Heather Nauert’s comments in yesterday’s press briefing that the department “always” seeks to work with Congress.