By Andrew Chung and John Kruzel

WASHINGTON (Reuters) – Conservative U.S. Supreme Court Justice Clarence Thomas has for decades accepted luxury trips from a Dallas businessman without publicly disclosing them despite a federal law requiring disclosure of most gifts, a media report said on Thursday, prompting Senate Democrats to call for an investigation.

The report by ProPublica found that Thomas has repeatedly vacationed with real estate magnate and Republican donor Harlan Crow, including on his private jet and superyacht in the United States and around the globe. The news outlet said the frequency of the gifts have “no known precedent in the modern history of the U.S. Supreme Court.”

Thomas and Chief Justice John Roberts did not immediately respond to a request for comment. The report raises new questions over potential conflicts of interest involving the justices and the court, which has endured escalating criticism for its lack of a formal ethics code.

Crow told ProPublica in a statement that he and his wife have been friends with Thomas and his wife since 1996 and have “never sought to influence Justice Thomas on any legal or political issue.”

Senate Judiciary Committee Chair Dick Durbin said his panel “will act” based on the report, without specifying what steps it would take.

“The highest court in the land shouldn’t have the lowest ethical standards,” said Durbin, a Democrat.

Durbin said the justices must be held to an enforceable code of conduct like other federal judges, who are instructed to avoid even the “appearance of impropriety.”

Roberts has said justices consult that code in assessing their own ethical obligations.

Democratic U.S. Senator Sheldon Whitehouse called on Roberts to ensure a robust investigation is carried out.

“This cries out for the kind of independent investigation that the Supreme Court — and only the Supreme Court, across the entire government — refuses to perform,” Whitehouse said on Twitter.

Gabe Roth, who heads the reform group Fix the Court, said lawmakers need to lead a “reimagining” of the court’s “responsibilities when it comes to basic measures of oversight.”

The ProPublica report is the latest revelation to prompt ethics concerns about Thomas. Previous reports of his wife Virginia “Ginni” Thomas’s involvement in efforts to overturn the results of the 2020 presidential election, along with Clarence Thomas’s decision not to recuse himself from election-related cases, raised questions about his judicial impartiality.

Thomas’s failure to report the trips provided by Crow appears to violate a federal law requiring justices, judges and other federal officials disclose most gifts, ProPublica reported, citing legal ethics experts.

Thomas, perhaps the court’s most conservative member, joined the bench for a lifetime appointment in October 1991 after being nominated by Republican President George H.W. Bush.

(Reporting by Andrew Chung in New York and John Kruzel in Washington; Editing by Andy Sullivan and Daniel Wallis)

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