Senate Democrats call on Chief Justice Roberts to investigate Thomas' undisclosed trips

Senate Democrats are calling for Supreme Court Chief Justice John Roberts to investigate the findings of a recent media report that detailed extravagant undisclosed trips taken by Justice Clarence Thomas that were paid for by a conservative billionaire.

Senate Judiciary Committee Chair Dick Durbin, D-Ill., and the 10 other Democrats on the panel said in a letter Monday that Roberts had a responsibility to look into a ProPublica article published Thursday that said GOP donor Harlan Crow had for years funded lavish trips for Thomas, one of the court's most conservative justices.

"We urge you to immediately open such an investigation and take all needed action to prevent further misconduct," the senators wrote.

The panel said that it plans to hold a hearing on the “need to restore confidence in the Supreme Court’s ethical standards" and that it would consider legislation to resolve those concerns.

According to the letter, Roberts previously denied a request from Durbin and some members of the Judiciary Committee in 2012 to adopt a resolution that would bind justices to a code of conduct that is applied to all other federal judges.

The 2012 request came amid reports of Crow's gifts to Thomas. In a year-end report on the federal judiciary in 2011, the court lauded its “jurists of exceptional integrity and experience” and said it "has had no reason to adopt the Code of Conduct as its definitive source of ethical guidance.”

The Supreme Court did not immediately respond to a request for comment Monday evening.

In a statement Friday, Thomas referred to Crow and his wife, Kathy, as “dearest friends" and said that early in his tenure he had been advised that "personal hospitality from close personal friends, who did not have business before the Court, was not reportable."

“I have endeavored to follow that counsel throughout my tenure, and have always sought to comply with the disclosure guidelines,” he said at the time.

Shortly before the ProPublica story was published, the Supreme Court announced that it had tightened its rules for what judges and justices need to include in annual financial disclosure statements.

Thomas said in his statement Friday that he would comply with the changes.

This article was originally published on NBCNews.com