Over English tea served in fine china cups at a sumptuous Paris apartment last November, an astonishing meeting took place to discuss the death of 36-year-old Diana, Princess of Wales.
The conversation was cordial. A butler carrying a teapot and tray of delicate sandwiches moved smoothly between the guests in the richly decorated drawing room of a building owned by the British Government, near the famous Champs Elysees.
In one Victorian armchair sat Lord Stevens, the respected former head of Scotland Yard. He had just finished a three-year investigation called Operation Paget into whether there was a conspiracy to murder the most famous woman in the world ten years ago and a cover-up to hide the truth.
The Princess was travelling with her Muslim lover Dodi Fayed in a Mercedes car when it smashed into the 13th column of the Pont D'Alma road tunnel in Paris at 12.23am on Sunday, August 31, 1997.
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Princess Diana: New evidence is to be heard at the inquest
She was mortally injured, dying in hospital three-and-a-half hours later. Dodi was killed instantly, as was the driver of the car, Henri Paul.
Since that moment, the controversy over Princess Diana's death has not abated. There is a veritable conspiracy theory industry which claims the Princess was assassinated, some even say at the instigation of the Royal Family or the British intelligence services because she was pregnant with Dodi's baby.
The report of Lord Stevens is now published. It concludes that Diana died in a tragic road accident. The report was meant to provide the final, unequivocal chapter on her death and a factual framework for her inquest which will begin next Tuesday.
Yet, if anything, the debate over how and why the Princess came to die is fiercer than ever. At the epicentre of this brouhaha is Lord Stevens himself.
For in the Paris apartment last November, he met the parents of the Mercedes driver Henri Paul for the first time. The couple must have been apprehensive.
No one in the Diana saga has been more vilified than their 41-year-old son. Within 24 hours of the accident he was being blamed for driving "like a lunatic" through the tunnel while "drunk as a pig".
Nevertheless, Giselle and Jean Paul, in their 70s, had bravely made the journey from their home in Brittany, on the west coast of France, to hear exactly what Britain's most famous policeman had to say about their son.
Lord Stevens soon put their minds at rest. The couple had hardly sat down before the peer assured them that Henri Paul had not been drunk - indeed, he'd had only two drinks that night.
As the meeting finished on November 8, 2006, the couple shook hands with Lord Stevens and went off with their heads held high. "We were pleased to hear our son was innocent as we always believed," Mr Paul senior told the Mail this week.
Yet a little over a month later the world was to hear a very different account from Lord Stevens. The 832-page Operation Paget report, compiled by 14 Scotland Yard detectives at a cost of £3.7 million, was published on December 14, 2006.
It declared that Henri Paul was driving at double the speed limit - 60mph - and had consumed a very considerable amount of alcohol before ferrying Diana and Dodi in the Mercedes from the Ritz Hotel in Paris to a private flat, where they were staying.
The driver was twice over the British drink-drive limit and three times over the French one. An expert cited in the report estimated that Paul had sunk the equivalent of ten small glasses of Ricard, his favourite liquorice-flavoured French aperitif, before taking the wheel.
If he had survived, he would be liable to prosecution for causing death by dangerous driving. It was a damning indictment of the dead driver, conflicting sharply with the account given by Lord Stevens to Henri Paul's mother and father.
Now grief can do terrible things to people's minds and it is possible Henri Paul's parents misunderstood or misheard Lord Stevens. However, detailed and contemporaneous notes of the meeting by an Operation Paget police officer suggest that this was not the case.
So why did Lord Stevens appear to have such a massive change of heart in less than five weeks? Did the policeman nicknamed Captain Beaujolais because of his love of fine wines come under pressure to change the conclusions of Operation Paget? It seems implausible.
Yet this troubling question has been aired at the preliminary hearings, overseen by High Court judge Lord Justice Scott Baker, for the forthcoming inquest on Diana and her lover.
Controversially, the judge - acting as coroner - will now order the jury to entirely disregard the Operation Paget report. It is a slap in the face for Lord Stevens. The contents have been removed from an official website linked to the inquest.
Lord Justice Scott Baker insists that 20 vital questions on Diana's death - and possible murder - still have to be answered.
They cover such matters as: whether Henri Paul was drunk or taking drugs; the possible pregnancy of Diana and why she was embalmed on British Embassy orders just an hour before her body was flown home to London, a process nullifying any later tests on whether she was expecting a baby; the presence, if any, of the secret intelligence service, MI6, in the French capital on the night she died; and the enduring mystery of why the Princess feared for her life.
Significantly, the judge has ordered that hundreds of explosive background documents, witness statements and tape recordings garnered during his investigation must now be made available to the jury. Some were not even alluded to in the Operation Paget report.
The background files cover the most contentious allegations surrounding the Princess's death.
For instance, a tape recording of one unnamed informant claims that the Queen's Private Secretary, Robert Fellowes, who was also Diana's brother-in-law, was in the French capital an hour before the crash and was seen in the telecommunications room of the British Embassy. (For his part, he insists he was at home in Norfolk all night.)
Another piece of evidence, detailed in a sworn witness statement from an American man, states categorically that Diana told a close female friend that she was pregnant just before she died, although she never named the father.
The files also delve deep into the lifestyle of Henri Paul. To understand his pivotal role, one must return to the days following the Princess's death.
The world was aghast. Flowers were heaped in Hyde Park, London, outside her home at Kensington Palace. Ordinary men and women wept in the streets across the globe.
Over in Paris, there was grieving too. Yet there was also something strange afoot. Within hours, rumours began to circulate that the driver of the Mercedes had killed the Princess.
By the Monday morning of September 1 - little more than a day after the crash - the French newspaper and television were publishing reports that Henri Paul had consumed "grossly excessive quantities of alcohol" and the speedometer of the Mercedes had jammed at 121mph. None of these stories was denied by the authorities.
Indeed, the allegations grew more detailed. On September 9 there were reports that a search of Henri Paul's flat in Paris had revealed a veritable drinking den. Shelves were groaning with bottles of spirits and wine. Tables were littered with bottles of vodka, Martini and fortified wines, while the kitchen contained open bottles of Ricard and American bourbon.
The reports contradicted what is now known to be the truth. An inspection of Henri Paul's flat by the detectives of the French Brigade Criminale much earlier - 48 hours after the crash - had found only copious bottles of soda water and just one bottle of champagne and a bottle of Martini.
Nevertheless the story that Henri Paul, a deputy security chief at the Ritz Hotel in Paris who had stepped in at the last moment to drive the couple, was a hopeless alcoholic gained credence.
Conspiracy theorists ask was he deliberately turned into the scapegoat? Was the driver, suspected of being a paid informant of the French and British intelligence services, used to cover up a much more sinister set of events?
Almost every person who talked to Henri Paul that night has since confirmed that he did not appear intoxicated before he set off into the Paris night.
Furthermore, a crucial blood sample taken from Henri Paul's suit jacket after his death - and the only one that has been firmly linked to him by DNA testing on his mother Giselle - shows no measurable trace of alcohol in his body.
In addition, a carbohydrate deficient transferring test 'proving' he was an alcoholic and conducted by the French authorities on Henri Paul after his death has also been undermined. A CDT test, the inquest will be told, is unreliable if performed on a dead body.
Meanwhile, what of the clutch of blood samples taken from his body in the days after the crash. They, apparently, showed that Henri Paul was hopelessly drunk. But were they really his own?
Intriguingly, they contained a medicine called albendazole, which the driver's doctor said he was never prescribed. It is a drug taken to get rid of tapeworms and given to downandouts on the streets.
Could they have come from a dead Paris tramp lying in the public mortuary alongside Henri Paul?
Equally puzzling is that the same clutch of blood samples revealed no sign of another medicine named acamprosate, which Paul had been prescribed. It is the only solid piece of evidence that he was a heavy drinker.
The driver was worried about his love of Ricard and had begged his doctor to give him the drug, designed to help alcoholics reduce their intake without cravings.
Pertinently, his doctor has since said that he felt Paul was worrying unnecessarily, as his drinking was moderate.
There is another dilemma, too.
The Henri Paul blood samples at the very heart of the Diana controversy reveal something else quite bizarre - that he had breathed in a very high quantity of carbon monoxide before his death: the same amount as a person committing suicide by putting a rubber hose from the exhaust through the window of his car.
Such a level would have left Paul visibly disorientated and almost certainly comatose. Yet at the Ritz that evening, minutes before he drove Diana, the CCTV cameras show him walking normally and even kneeling down to retie his shoe laces and gracefully standing up again.
It is now accepted that he never drew breath after the crash, ruling out the possibility that he inhaled poisonous exhaust fumes. Significantly, Dodi's blood was tested and was shown to contain no carbon monoxide.
The tainted blood samples remain - as Lord Stevens and toxicology experts say in the Operation Paget report - a complete mystery. One possible explanation is that they are not the driver's blood at all but come from someone else in the public mortuary who had committed suicide that weekend.
So were the samples tampered with? Were they mistakenly, or deliberately, swopped with those from another corpse?
The first samples of blood taken from the driver's body were left unattended and unlabelled in a fridge at the mortuary for more than a day until Monday, September 1.
So what will happen next? Lord Stevens is to be called as a witness at the inquest. He will be asked by lawyers for Henri Paul's family about the 'gross discrepancy' between the soothing account he gave in the Paris apartment on their son and the one contained in the official Operation Paget report.
He is also likely to be quizzed on the plethora of evidence on Diana's death never included in his final report. Of particular concern is the testimony of a Paris jeweller, who sold Dodi an engagement ring on the day before the crash, sparking theories that the playboy was about to propose to Diana.
Of course, Diana might well have turned down any such marriage. But the jeweller, in a written complaint, says that he was pressured - unsuccessfully - by the Paget detectives to change his tale and say it was just a 'friendship' ring. There are other worrying matters too. The preliminary inquest hearings have revealed that important eyewitnesses of the crash - including those claiming there was a blinding flash in the tunnel and that they saw a mystery white Fiat Uno at the scene which may have deliberately clipped Diana and Dodi's Mercedes, causing the accident - were never interviewed by Lord Stevens' team.
Instead, his detectives relied heavily on old statements made years ago to the French police. Now Lord Justice Scott Baker has ruled that crash onlookers and other witnesses should give evidence via video links from Paris and in person at the London inquest. The jury will be taken to the accident site in the Alma tunnel in the French capital.
One important new witness will be a French fireman, Christophe Pelat. He discovered the body of a paparazzi photographer named James Andanson - thought by conspiracy theorists to have been driving the white Fiat Uno - in a remote woodland with a shot in the head three years after the crash.
It was always said that Andanson had committed suicide after marital problems.
The photographer amassed millions selling photographs of Diana and is suspected of tipping off British, American and French intelligence services on the Princess's movements during her last holiday.
Andanson gave conflicting accounts of his movements to French police. They concluded that he was not in Paris on the night of the crash, although he had chased the couple relentlessly as they cruised on Dodi's yacht the Jonikel in the days beforehand.
Why, one might ask, would he have stopped following her when there was still money to be made?
The evidence of Christophe Pelat is vital. It might indicate that Andanson knew the truth and was disposed of. Yet the fireman's name and testimony - just like those of many others - appeared nowhere in the Operation Paget report in what was billed as the definitive account on Diana's death.
Of course, all this must be somewhat discomforting for Lord Stevens. As a life peer and now an international security adviser to Gordon Brown, he moves in the upper echelons of society with a hitherto untarnished halo as a formidable investigator.
Meanwhile, Lord Justice Scott Baker faces the challenging task of guiding a jury through a monumentally complex inquest. For if the 12 men and women leave their verdict open - if there is no conclusion on the cause of the Princess's tragic death - there will have to be a police inquiry.
Yes, a second one. When will the spirit of Diana be allowed to rest?
Article originally published here.