Almost 40 per cent of the British population tuned in to Princess Diana's 1995 interview with Martin Bashir on the BBC's Panorama programme. Screenshot / BBC
OPINION:
Prince Harry and Earl Spencer could hardly have been clearer. Princess Diana's landmark appearance on Panorama in 1995 led to her death.
Martin Bashir's "interview of the century" – as it was boastfully billed by the BBC at the time – attracted an audience of 23 million viewers, and had profound and far-reaching consequences for the royal family.
And, according to her younger brother and her youngest son, it also proved to be Diana's fatal mistake.
Their clear inference was that, had she not been persuaded to invite Bashir into her sitting room at Kensington Palace, she would not have met her death two years later in a car accident in Paris.
But a doe-eyed Diana, Princess of Wales, did pour her heart out to the then 32-year-old reporter from the BBC's flagship current affairs programme, in a 54-minute interview in which she discussed everything from her failed marriage to the Prince of Wales, from whom she had separated in 1992, to her battle with "rampant bulimia" and self-harming behaviour.
Almost 40 per cent of the British population tuned in as the princess uttered the immortal line about there being "three of us in this marriage", a reference to her husband's extra-marital affair with Camilla Parker Bowles.
But an excoriating report published last week by Supreme Court judge John Dyson, into the monstrous journalistic methods that enabled the Panorama team to set up the interview in the first place, accused Bashir of using a battery of "deceitful behaviour" to get her on side, including commissioning fake bank statements and other documents to falsely suggest individuals were being paid to keep the princess under surveillance.
There is little doubt that the incendiary interview proved to be a catalyst for a catastrophic chain of events that culminated in Diana's untimely death. But while it won her a great deal of short-term public sympathy, it also alienated her from senior figures in the Royal household and played into the hands of critics who claimed she was "unhinged".
Certainly, the Queen was so horrified by her daughter-in-law's actions, shortly after the interview was broadcast she told Sir Richard Eyre, former director of the National Theatre, that Diana had done a "frightful thing".
Exactly a month later, the monarch ordered both Charles and Diana and the Duke and Duchess of York – who had also separated in the so-called 'annus horribilis' of 1992 – to finally get a "double" divorce in 1996.
Without Panorama, would things have escalated so quickly – and irretrievably?
Now effectively frozen out of royal circles, Diana began briefing even harder against the royal family, with ever more outlandish false claims – that the Queen, suffering from cardiac problems, was to abdicate; that Prince Edward was receiving treatment for Aids; and that she herself would be murdered, in a plot masterminded by her estranged husband, probably carried out by sabotaging the brakes of her personal car.
Bashir has always denied being the source of Diana's defamatory statements, insisting that she spoke to "mystics and clairvoyants" who could have fed the made-up stories to her.
But it was Diana's false allegation that her husband had got their children's nanny, Tiggy Legge-Bourke, pregnant and then paid for an abortion that proved to be the final straw for the princess's long-standing private secretary, Patrick Jephson. Still smarting from being kept in the dark over her Panorama interview, he resigned in January 1996 after eight years in the post.
Jephson later revealed that Diana only told him about having spoken to Bashir a week before the broadcast, and was "not at all confident about what she had done".
He said: "It triggered that part of her which was not rebellious or given to dangerous stunts, which was actually conventional and dutiful, and responsible and awake to her broader royal responsibilities."
As her family and friends have testified on numerous occasions, there was a side of Diana that was extremely loyal. She sent out charming thank-you letters for the tiniest of presents and the briefest of lunches. Her upbringing had trained her not just in etiquette but in the selfless, thoughtful behaviour that springs from genuine, deeply rooted manners.
Again and again, hard-bitten journalists, who had been happy to bash her in the papers, melted on meeting her and encountering her shy charm.
She forged friendships with some seemingly unlikely allies, including the late Prince Philip. As Gyles Brandreth writes in his new book, Philip: The Final Portrait: "Her friends Rosa Monckton and Lucia Flecha de Lima are quite clear on this: she had great respect and affection for her father-in-law; she trusted him and knew he wanted only to help."
Her inner circle of friends was, in turn, incredibly loyal to Diana. Had she stuck solely with those friends, who knows what her future could have been?
Following her divorce, an increasingly detached Diana then embarked on a series of ill-advised relationships with men. Her decision to date Dodi Fayed, son of Harrods boss Mohamed Al-Fayed, had led to a flaming row with her mother, Frances Shand Kydd, whom her former butler Paul Burrell revealed had accused her daughter of behaving like a "whore".
The Princess had also fallen out with her brother, Earl Spencer, her sister-in-law Sarah Ferguson, and other close confidantes including Sir Elton John. She only made it up with the singer at the funeral of the fashion designer Gianni Versace a month later in July 1997.
Much has been made of Diana's disastrous decision to get rid of her Scotland Yard bodyguards – against the advice of her long-time royal protection officer, Ken Wharfe.
Many have suggested that her Metropolitan Police detail would not have allowed her to be driven without wearing a seatbelt, let alone to be chauffeured by Henri Paul, the acting security manager of the Hotel Ritz Paris (owned by Fayed), who, it later emerged, was under the influence of alcohol.
Her personal bodyguard, Trevor Rees-Jones, was the only person to survive the crash in the early hours of that Sunday morning.
According to veteran royal reporter Phil Dampier: "Because Diana died as this iconic young woman, people tend to put her on a pedestal. But, actually, in the run-up to the Paris car crash she was an unguided missile."
By then, she was living at Kensington Palace, aged 36. She was young enough to have a fresh start at life. Yes, there would have been huge media attention, but that would have mellowed with time as the focus turned on to the next generation.
In a sign that she was putting her past behind her, in June 1997, she held a sale of her dresses at Christie's in New York, raising US$3.25 million for charity. She could have lived the admirable life of a philanthropic grande dame, punctuating her charity work with jolly holidays, chatty Mayfair lunches and shopping expeditions with her friends – and perhaps a return to the sort of outdoorsy life in the country she had enjoyed as a child.
But it was not to be. As Dampier says: "She had become increasingly isolated and was convinced she was being spied on. Burrell described how she made him rip up the floorboards at Kensington Palace, looking for bugs."
Diana's biographer Tina Brown suggests that, towards the end of her life, there were hints of the Diana that she could have been, had she not been caught up in the storm of that tell-all interview. While Diana herself described 1996 as "the worst year of my life", actually she was beginning to get back on track.
According to Brown in her 2007 book, The Diana Chronicles, in the weeks leading up to her death, the Princess had not only reconciled with Charles, but even "accepted" Camilla Parker Bowles.
"She still wished that her marriage could have survived," Brown told The Telegraph last November. "She didn't say: 'I'm so happy to be divorced…' She said: 'We would have made a great team.'"
Whether that was the case, we'll never know.
* Additional reporting by Harry Mount
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