Sen. Dick Durbin (D-Ill.), the chairman of the Senate Judiciary Committee, declined to tell a reporter or Sen. Marsha Blackburn (R-Tenn.), who wants the subpoena issued, that he would support the effort.

Ms. Blackburn, in late November, tried bringing forth an amendment for a vote that would authorize the subpoena but was blocked by GOP colleagues, who invoked a rule that led to the hearing ending after about two hours.

When Mr. Durbin was asked on Dec. 5 whether he'd issue the subpoena, he demurred.

"I don't know anything about his flight logs. I know who Epstein was but I certainly don't know anything about the issue," he told a Fox News reporter in Washington.

Mr. Durbin also falsely said that the matter "has never been raised by anyone."

After entering a committee hearing in which members questioned the FBI's director on various topics, Mr. Durbin told Ms. Blackburn that he was not aware that one of her amendments was a subpoena for Mr. Epstein's flight logs.

"I do not know anything about this request," he said.

An aide for Democrats on the Senate Judiciary Committee earlier this month acknowledged that Ms. Blackburn's attempt to issue the subpoena was blocked during the Nov. 30 committee hearing before noting that Republicans, led by Ranking Member Sen. Lindsey Graham (R-S.C.) invoked a rule that ended discussion on amendments for the subpoenas that were ultimately approved for a billionaire and conservative activist linked to Supreme Court justices.