Ian Maxwell is adamant his sister will not call the Duke of York as a witness when she stands trial this summer.
He is casting his mind back to Prince Andrew's last public interrogation - by journalist Emily Maitlis on BBC's Newsnight - and considers it a bad idea for him to spring to Ghislaine Maxwell's defence.
"It was the most remarkable piece of self-destruction," he says. "As he proved in that interview, I think he's a pretty serious hostage to fortune."
Maxwell, 64, is giving a wide-ranging interview in defence of his younger sister, 59, whom he believes has become a hate figure in part because she is a woman accused of sex crimes.
He claims she is being treated far worse before trial than men such as Harvey Weinstein and Bill Cosby, who were both convicted of sex offences.
Maxwell has written a letter to US President Joe Biden's attorney general, pleading for the US to give his sister a fair trial.
In it, he compares her plight and that of Field Marshal Lord Bramall, a former head of the Army and D-Day veteran who was falsely accused of being a paedophile by a fantasist who was subsequently jailed for 18 years.
Ghislaine Maxwell, he says, risks becoming a victim of a miscarriage of justice for the sex crimes committed by her one-time boyfriend Jeffrey Epstein, the billionaire financier, who committed suicide in 2019 while awaiting trial for child sex abuse.
His sister is languishing in a New York jail on charges relating to allegations that took place - in some cases - 27 years ago, made by four women whose identities the courts will not reveal.
Ian Maxwell has likened the "truly horrific" conditions of her captivity in a 9ft by 7ft cell to "torture" and questions how she can mount a defence in such circumstances.
"My sister has been banged up for 280 days. It really is grotesque," he says. When - or if - she is acquitted, he adds, she plans to campaign for the half a million people who spend month after month on pretrial detention in the US.
The British socialite was told this week she faced two further charges of sex trafficking of a minor after a new woman came forward claiming Maxwell procured her for Epstein. In total, she faces eight charges.
Ian Maxwell insists there is not a shred of evidence to corroborate the historical allegations, and the new charges suggest the US prosecutor's case is a weak and desperate one.
He points to testimony given by a police officer in a civil case against Maxwell who, under oath, said her name had never come up in a previous criminal investigation into Epstein dating back to a conviction in 2008.
Maxwell, says her brother, is in a quandary. If she delays her trial - due to start in July - to prepare a defence against the new allegations, she will spend more time in jail. A fourth attempt to secure her bail is under way.
In his letter to US Attorney-General Merrick Garland, Maxwell complains of the repeated decisions to block bail, but adds: "What is most puzzling is the court's refusal to identify the now four anonymous complainants who only stepped forward after Epstein's death, 25 years after the offences were alleged to have been committed.
"Given the anonymity of the accusers, she [Ghislaine Maxwell] is unable to prepare her defence, simply because she doesn't know who they are and of what she is accused."
He draws parallels with Operation Midland, the British police investigation in which Carl Beech falsely accused a number of high-profile men of being involved in a murderous paedophile gang.
"The reason that I raised it [Operation Midland] is simply that here we have a situation where we have now four anonymous accusers," says Ian Maxwell in a Zoom interview from his London home.
"Their allegations have never been put to the test, no cross-examination, no evidence furnished, no names provided. It's completely Kafka-esque. You don't know who's accusing you; you don't know what you're accused of specifically; you don't know when it's alleged to have happened, other than it did happen."
He criticises prosecutors and the FBI for staging what he calls a "dog and pony" show to announce Maxwell had been captured last July at a remote home in New Hampshire.
What followed was, he says, "an outrageous perp walk of a press conference, designed to be prejudicial - and it's been highly successful. If you look at the headlines, Ghislaine is a 'monster' or a 'madame' or whatever else she has been described as, and it's grotesque and really offensive."
He doesn't recognise the depiction of her as a sexual predator and procurer of girls and young women. "We grew up together in England, seeing a lot of each other, and she has the right values. You couldn't be a child of Bob Maxwell and be some kind of floating socialite, doing nothing."
Their father, the publishing tycoon Robert Maxwell, fell overboard and died off his yacht in November 1991, leaving behind a business empire in tatters. People have tried to draw a connection between father and daughter, suggesting they both had "bad genes", but that is unfair, says Ian Maxwell.
The last time he heard his sister's voice was nine months ago, listening to her give monosyllabic answers at an early court hearing that was viewable online. She has lost weight - and even her hair - while in jail and communicates through her lawyers.
Ghislaine Maxwell has insisted her relationship with Epstein was not a normal boyfriend-girlfriend relationship and that they maintained separate homes.
"I don't think you could characterise this as a kind of conventional lovey-dovey, living-together relationship," her brother says.
"They never lived together, ever. He had his place; she had her place. It's hugely important for a man who was as compartmentalised as Jeffrey Epstein clearly was."
Epstein, he believes, kept his sordid sex life and criminality secret from Maxwell.
Dozens of women have filed lawsuits against Epstein's estate, valued at close to US$600 million (NZ$853m) on his death. To date, four women are involved in the criminal prosecution of Maxwell. It is unclear if others will give supporting evidence.
The new charges had the effect of "lobbing a grenade into the proceedings", Ian Maxwell says.
"Ghislaine is facing charges effectively created by the US government solely to satisfy the media, to appease accusers, and their trial lawyers, bolstering a weak case in an effort to justify huge settlements for crimes committed by Jeffrey Epstein, and by Jeffrey Epstein alone.
"They're trying to revive Epstein by re-litigating crimes, with a proxy defendant, Ghislaine. That just ain't right."
The latest charges relating to sex trafficking between 2001 and 2004 are intriguing, not least because that is when Prince Andrew, Maxwell's long-time friend since her Oxford days, was becoming close to Epstein. The pair met around 1999.
Prince Andrew gave the Newsnight interview in November 2019, three months after Epstein died. In it he denied any wrongdoing but failed to express sympathy for Epstein's victims and argued that the account of one victim, Virginia Roberts Giuffre, was false because he did not sweat and had anyway been at a Pizza Express restaurant.
The claims opened him up to ridicule, but Ian Maxwell doesn't believe that interview had any bearing on the subsequent pursuit of his sister. The die was cast when Epstein died in custody, says Ian Maxwell, and the authorities - William Barr, then-US attorney general, was "livid" - needed somebody in the dock, he maintains.
"I don't actually agree that this particularly reignited [the case]," he says. "It [the interview] did sort of shine a light back on it, but it was the most remarkable piece of self-destruction."
Prince Andrew and Ghislaine Maxwell last saw each other in June 2019. In almost two years since then their lives have been turned upside down through their association with Epstein. The Duke is banished from public duty; Maxwell is confined to her jail cell.
A trial, should it take place in July, will decide once and for all if she deserves anyone's sympathy.