Ian Maxwell told BBC Radio 4’s Today programme that his sister was losing her hair and struggling with her eyesight as she awaits her trial which is due to start in July.
He said Ghislaine ‘remained resolute’ but was being served ‘brown’ water, ‘inedible’ food and monitored around the clock in ‘grotesque’ conditions in Brooklyn which he said were ‘not the way that a democratic country’ should run its prisons.
A US judge has twice denied bail to Epstein’s ex-girlfriend, saying she ‘plainly poses a risk of flight’ – but Mr Maxwell insisted she would not seek to flee if her third bail application is successful.
He also did not rule out that Prince Andrew could be called to speak in her defence, saying he ‘assumes’ that Maxwell still considers the Duke of York as a friend.
Ghislaine Maxwell (a sketch of her video link court appearance last year) faces child sex trafficking charges over allegedly recruiting three teenage girls as young as 14 for paedophile Jeffrey Epstein to sexually abuse in the 1990s
Ian Maxwell (right) with Ghislaine Maxwell (second left) and their father, the late British publishing tycoon Robert Maxwell (second right) and his wife Elizabeth (left) in 1990
Mr Maxwell said his sister had offered in her latest bail application to renounce her French and UK citizenships, which she said was ‘no easy thing’ for her.
Prosecutors had argued that Maxwell, who also has US citizenship, might flee to Britain or France and evade extradition if she was released.
They also pointed to Maxwell’s vast wealth – but her brother said she was willing to put her money under the supervision of US authorities if it helped secure bail.
‘Had she wanted to run away, she could have run away at any point in the year after Epstein died,’ Mr Maxwell said. ‘But she remained permanently in the United States.
‘This isn’t somebody who’s seeking to flee. She has attachments here, she has family here, she has an entire life built by her for 30 years here.’
Her lawyers had offered $22.5million in bail posted by the defendant and her husband, but the judge rejected the second bail package in December.
‘No conditions of release can reasonably assure the Defendant’s appearance at future proceedings,’ federal judge Alison Nathan wrote.
‘Ghislaine has been in prison now for nearly 250 days and counting. She is in effective isolation in a cell that measures 6ft by 9ft and which includes a concrete bed and a toilet,’ Mr Maxwell said.
‘There is no natural light. She is under 24-hour, round-the-clock surveillance with ten cameras including one that moves and tracks her movements. That is her existence.
‘The water that is provided through the prison is brown and the food that she’s given is very highly microwaved and basically inedible.
‘She is resolute, she’s strong in her spirit and undaunted, but obviously this is very, very wearing physically.
‘She’s a 59-year-old woman and we understand that she’s losing her hair, and she’s also having trouble with her eyesight and her ability to concentrate because this is a tremendous pressure to be under.’
Asked whether the conditions were not necessary to prevent her from harming herself – like Epstein – Mr Maxwell said his sister ‘has never been a suicide risk’.
‘There are daily evaluations of her, she has shown no indication that that is her intention. She is being completely overmanaged,’ he said.
But he added: ‘I’m worried about her health and her ability to concentrate and to mount her defence. No human being should have to go through what she’s been through.
‘It is really degrading, and in terms of the deprivation of sleep, this is not the way that a democratic country should be running its prison system, it’s grotesque and in that respect it amounts to torture.’
Maxwell is being held at the Metropolitan Detention Center in Brooklyn (pictured), and faces up to 35 years in prison if convicted
Ian Maxwell did not rule out that Prince Andrew, pictured during his disastrous interview with BBC Newsnight in 2019, could be called to give evidence in Ghislaine Maxwell’s defence
Mr Maxwell also slammed prosecutors for allegedly failing to hand over details of the three accusers who are the subject of the case.
Ghislaine Maxwell has pleaded not guilty to helping Epstein recruit and groom underage girls for sex in the mid-1990s, and not guilty to perjury for denying involvement.
Asked whether he wished he had intervened to end his sister’s relationship with Epstein, Mr Maxwell said: ‘I wish she’d never met the man, obviously.
‘But we don’t live on the same continent, we don’t have the same social life, we don’t have the same friends. I’m not in the business of talking to my sister about her private life.’
Questioned about whether Prince Andrew could be called as a defence witness, Mr Maxwell said: ‘I can’t answer that, I just don’t know’.
But asked if she still considers Andrew a friend, he said: ‘I don’t know. I would assume that she does, yes’.
Andrew acknowledged in his disastrous BBC interview in 2019 that he associated with Maxwell and Epstein over a number of years until Epstein’s conviction in 2008.
After Epstein was released from jail, Andrew again went to visit him in New York in what he now claims was a visit intended to end their relationship.
In 2019, Epstein was arrested on new sex-trafficking charges and killed himself in a Manhattan jail in August that year while awaiting trial.
Maxwell subsequently went to ground and her whereabouts were a mystery for nearly a year after Epstein’s death until she was arrested in New Hampshire last July.
She is being held at the Metropolitan Detention Center in Brooklyn, and faces up to 35 years in prison if convicted.