The U.S. Senate Finance Committee on Wednesday released a report detailing how embattled Supreme Court Justice Clarence Thomas may have had a substantial amount of a loan for a luxury RV forgiven by a wealthy friend—which one watchdog called “a serious ethics issue.”

The panel’s probe was sparked by New York Timesreporting from August about Anthony Welters loaning Thomas money to buy a used Prevost Le Mirage XL Marathon, or “the Rolls-Royce of motor coaches,” which cost $267,230 in 1999. Welters told the newspaper that “the loan was satisfied” and provided a photograph of the title with his signature and a handwritten “lien release” date of November 22, 2008.

The Senate memorandum states that “while additional documents pertaining to the loan agreement may exist, documents reviewed by Democratic staff suggest that Justice Thomas did not repay a significant portion of the loan principal. In fact, none of the documents reviewed by committee […]