Senate Judiciary Committee member Sen. Sheldon Whitehouse displays a copy of a painting featuring Supreme Court Associate Justice Clarence Thomas alongside other conservative leaders during a hearing on Supreme Court ethics reform in the Hart Senate Office Building on Capitol Hill on May 02, 2023 in Washington, DC.
CNN  — 

Senate Democrats rejected Thursday an offer from by GOP megadonor Harlan Crow to supply the Judiciary Committee with some information related to the travel and luxury vacations he gifted to Justice Clarence Thomas over the past five years.

In a letter signed by the committee’s Democratic majority, the senators said Crow’s proposal is an insufficient “partial” compromise to the committee’s questions that would leave out information they believe necessary to “inform the Committee’s ongoing legislative efforts” for Supreme Court ethics reform.

Crow’s relationship with Thomas has been under the spotlight since ProPublica published a series of reports detailing luxury travel that Thomas received from Crow, as well as a private 2014 real estate deal with Thomas’ family. The real estate transaction and the bulk of the hospitality went unreported on Thomas’ annual financial disclosures, as did Crow’s reported payments for the tuition of a grandnephew of Thomas. Earlier this fall, Thomas amended past disclosure reports to reflect more trips with Crow as well as the real estate deal.

Thursday’s letter reveals that a lawyer for Crow had agreed to provide information to the Senate Judiciary Committee covering only the last five years of their friendship. The proposed response would not include – as the committee had requested – an itemized list of all gifts, payments and items of value exceeding $415, as well as real estate transactions between the two men over their more than two-decade long friendship.

In exchange for the information, according to the letter, the committee would have to “forego any further inquiries” into Crow’s dealing with Thomas, including follow-up questions.

“Receiving only partial responses during this arbitrary time period is insufficient to inform the Committee’s ongoing legislative efforts,” Senate Judiciary Chairman Dick Durbin wrote in a letter signed by nine other members Thursday. He added that Crow had until October 19 to put forward a renewed offer.

“It is disappointing that after many months of good faith efforts to voluntarily cooperate with the Judiciary Committee despite serious constitutional concerns about its inquiry, members of one party forced the committee to reject a mutually respectful compromise,” the Office of Harlan Crow said in a statement.

“The committee’s rejection of a reasonable compromise offered in the spirit of transparency underscores that this is a political campaign designed to discredit a sitting Supreme Court Justice and not a legitimate effort to legislate,” the statement said.

Last spring, Michael Bopp, a lawyer for Crow, questioned whether the committee has the authority to launch such an investigation because, he said, it lacks a valid legislative purpose. He said he would meet with staff to discuss questions regarding the interactions between his client and Thomas.

“We respect the Senate Judiciary Committee’s important role in formulating legislation concerning our federal courts system, and would welcome a discussion with your staff,” Bopp wrote.

Over the summer there had been sporadic meetings between lawyers and staff, according to a source, but Thursday’s letter marks a new escalation of tension as the justices have started a new term.

The committee also sent letters to conservative activist Leonard Leo, who refused last summer to provide Democratic lawmakers with information regarding his interactions with Justice Samuel Alito, who attended a luxury fishing trip with him in 2008 and took a ride on a private jet owned by a conservative hedge fund manager. In a letter in July, Leo’s lawyer said the congressional inquiry “exceeds the limits placed by the Constitution on the Committees investigative authority” and is tainted by partisan politics.

The senators rejected Leo’s arguments that the committee’s inquiry amounted to political retaliation – calling the charge a “frivolous mischaracterization.”

“Specifically, the Committee has been examining how the current ethical framework governing federal judges fails to capture the full scope of previously undisclosed gifts, transportation and lodging made available to Supreme Court justices by parties with business before the Court,” the Democrats wrote.

CNN has reached out to Leo for comment.