US Supreme Court Justice Clarence Thomas has acknowledged he took three trips aboard a Republican mega-donor's private plane last year, as an ethics row grips the nation's top court.
The conservative judge said failing to previously report receiving such hospitality had been "inadvertent".
Supreme Court jurists are required to file annual financial disclosure forms.
Justice Thomas was among the last to do so, but he is not the only one facing potential conflicts of interest.
Other justices, including Sonia Sotomayor, a liberal, and Samuel Alito, a conservative, have come under scrutiny in recent months.
Critics are pushing to adopt a new ethics code for the nine justices, who receive lifetime appointments to the nation's highest judicial body.
Justice Thomas' disclosure on Thursday follows US media reports that the 75-year-old had failed to disclose several expensive gifts from Harlan Crow, a wealthy real estate developer and conservative benefactor.
ProPublica, an investigative journalism non-profit, reported that Mr Crow had paid for private school tuition for a child raised by the judge, purchased the Georgia home where the judge's mother resides, and has lavished him with luxury trips for more than two decades.
Under the rules for sitting members of the US federal judiciary, a Supreme Court justice should list the "personal hospitality of any individual" as a gift.
But before Justice Thomas' disclosure report, he had reportedly failed to divulge several such gifts, raising questions over whether Mr Crow could have leveraged their friendship to influence business before the court.
Justice Thomas' attorney said in a statement that the ethics complaints stemmed from "left wing 'watchdog' groups" who were "motivated by hatred for his judicial philosophy".
"He has never accepted a gift from anyone with business before the Court," Elliot S Berke wrote.
"For anyone who knows him at all, it is clear that no-one influences Justice Clarence Thomas' jurisprudence. But friends are dear, close, and separate."
Accusing critics of "political blood sport", Mr Berke said there had been "no wilful ethics transgression, and any prior reporting errors were strictly inadvertent".
Mr Berke added that the judge may seek to amend prior reports to include disclosures he had previously thought he did not have to report.
Of the three trips detailed in Thursday's report, one was to Mr Crow's mountain lodge in upstate New York and two were to a conservative conference in Texas.
Justice Thomas reportedly visits the New York lodge every year, but the disclosure says his 2022 travel there took place amid concerns for his safety after the court's draft opinion overturning abortion rights nationwide was leaked to the public.
Court officials recommended that he avoid commercial travel, Justice Thomas says.
Justice Alito has also come under scrutiny for failing to report private paid-for trips.
ProPublica wrote in June that the 73-year-old went on a 2008 fishing trip to Alaska with hedge fund billionaire Paul Singer, who has repeatedly had business before the Supreme Court in the years since.
Justice Alito has vigorously defended himself against what he calls "misleading" claims, appearing thrice in the op-ed pages of the conservative-leaning Wall Street Journal.
His 2022 report acknowledges a trip to Rome paid for by a conservative group that has participated in religious liberty cases at the top court since 2020.
The heightened focus on court ethics has also drawn other potential lapses by Supreme Court members into its dragnet.
Staff to Justice Sotomayor promoted her literary career through visits to colleges and libraries, according to the Associated Press.
Justice Sotomayor also did not recuse herself from three cases involving Penguin Random House, which had paid her more than $3m (£2.4m), reports CNN.
Conservative Justice Neil Gorsuch also reportedly did not recuse himself from a case involving the publisher, who has published a book of his.
And the wife of Chief Justice John Roberts has made more than $10m as a legal recruiter for firms that practise before the court, Business Insider reported.