Democrats on the panel investigating the 2012 Benghazi attacks are accusing Republicans leading the probe of selectively releasing information to embarrass former secretary of state Hillary Clinton as she runs for president.

In a letter to Select Committee on Benghazi Chairman Trey Gowdy (R-S.C.) on Wednesday, panel Democrats asked that he release the transcript from Tuesday’s deposition of Clinton confidant Sidney Blumenthal to provide context for e-mails he sent her in 2012 when Clinton served as secretary of state. Republicans have said they plan to release the e-mails within a week.

“It has become impossible to understand your revolving policy on when the Select Committee will release information and when it will not,” the panel’s Democratic members, led by Rep. Elijah Cummings (D-Md.), wrote Gowdy. “This type of incoherent policy inevitably leads to criticisms that the investigation is motivated by a partisan political attack against former Secretary Clinton rather than a neutral effort to obtain the facts.”

Democrats said Blumenthal was called to testify not because he had any insights to share on the attacks and their aftermath, but because he’s a political ally of Clinton — a characterization Republicans reject.

The letter lays bare the partisan tension surrounding Gowdy’s probe of the September 2012 attacks by militants on a diplomatic compound and CIA annex in Benghazi, Libya — which left four dead, including U.S. Ambassador Christopher Stephens — and its heavy focus on Clinton.

Blumenthal on Friday provided the committee with roughly 60 previously unknown e-mails between himself and Clinton. The public release of those e-mails, which remain private, is the latest partisan flashpoint illustrating the depth of disagreement between the two sides over Gowdy’s approach since the special committee was created in May 2014.

Tuesday marked its first deposition, a significant moment for the former federal prosecutor.

Gowdy argued this week that Democrats must assent if he is to release the new e-mail cache within five days. Democrats say this rule is nonsense and that they were never consulted about the matter.

Cummings accused Gowdy on Tuesday of seeking to create a negative media narrative about Clinton by repeatedly leaking snippets of information from the Benghazi probe to the press.

“What we’re looking for is the truth,” Cummings told reporters on Tuesday outside the deposition room where Blumenthal was being questioned. “If you’re dealing with the truth, you don’t have to leak. You don’t have to leak. You just put it all out there.”

This criticism now centers on the deposition transcript, which Democrats argue must be published along with the new e-mails.

Gowdy suggested Tuesday that he will not release the transcript.

“We haven’t done it with any other witness, so I need Mr. Cummings to explain to me why we should treat this witness differently,” he said.

In a sign that they agree on almost nothing related to the probe, Cummings wrote that Gowdy was the “one treating Mr. Blumenthal differently” be releasing his emails.

The deposition revealed that Blumenthal passed memos to Clinton about the state of affairs in Libya written by a third party, whom Gowdy told Fox News on Tuesday was former high-ranking CIA official Tyler Drumheller.

Blumenthal, describing himself as a “longtime friend” of Clinton’s, suggested the material was part of a casual correspondence and that the former secretary of state was at liberty to ignore his correspondence.

“I testified about sending some reports by a respected, high-ranking former CIA official that I thought might be informative to Secretary Clinton for her to use, or not, as she saw fit,” he said.

Speaking after the deposition, Gowdy painted Clinton as a leader who was more interested in insights from her network of connections than in using material vetted by intelligence agencies.

He argued it was irresponsible of Blumenthal to pass intelligence to Clinton without fully vetting its author’s sources.

“We have an intelligence apparatus,” Gowdy said. “My interest is: why send it to the secretary of state? Why not send it to the CIA?”