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A long-awaited British police report into Princess Diana's death due this week could finally lay to rest conspiracy theories that she was murdered rather than that she died the victim of a tragic accident.
More than nine years after Diana and her lover Dodi al Fayed were killed in a high-speed car smash in Paris, a three-year inquiry headed by Britain's former top police officer Sir John Stevens is expected to announce on Thursday it has ruled out foul play.
However that is unlikely to quash theories that British spies or even her ex-husband, heir-to-the-throne Prince Charles, had plotted the accident because the couple's relationship was embarrassing the royal household.
The top-level police investigation was ordered by former Royal Coroner Michael Burgess in January 2004 when he opened a British inquest into Diana's death.
"I am aware that there is speculation that (her death was) not the result of a sad but relatively straightforward road traffic accident in Paris," Burgess said at the time.
Stevens, who headed London's police force, has spent almost three years investigating what happened, interviewing Charles for several hours as part of his inquiry which he said aims to draw a line under the issue.
In May, he said he had found new witnesses and gathered fresh forensic evidence, but security experts expect him to back official French findings that the deaths were an accident.
Diana, who was 36, and al Fayed died after their chauffeur-driven Mercedes limousine smashed into the wall of a road tunnel in the French capital in August 1997 after they sped away from the Ritz Hotel whilst being pursued by paparazzi on motorbikes.
A two-year inquiry by French authorities in 1999 ruled that al Fayed's driver Henri Paul, who was also killed, was to blame because he was drunk and driving too fast.
But conspiracy theories still abound. They suggest that Diana was pregnant at the time and that she and al Fayed were planning to marry.
There have been claims Paul was dazzled by a blinding light while there has also been much speculation about a mysterious Fiat Uno car which Paul swerved to avoid before the crash.
French judges said the Mercedes had grazed the slow-moving white Uno, but the car was never traced despite a massive hunt.
Conjecture was further fanned in 2004 by revelations that Diana had written a letter to her former butler Paul Burrell 10 months before her death in which she said she suspected Charles was trying to kill her.
"This particular phase in my life is the most dangerous," the letter said, according to excerpts leaked to the British media. "My husband is planning 'an accident' in my car, brake failure and serious head injury."
Al Fayed's father Mohamed, multi-millionaire owner of the exclusive London store Harrods, has campaigned ever since the deaths for a full public inquiry to be held into the events.
"It is absolute black and white horrendous murder," he said.
However suggestions of a murder plot have been dismissed by witnesses, officials and royal commentators.
They argue that it has simply been too hard for some people to accept that the untimely death of one of the world's most glamorous and iconic figures could be just an accident.
The death of the "people's princess", as Prime Minister Tony Blair dubbed her, led to a public outpouring of grief unprecedented in Britain in recent times.
Eyewitness Mohamed Medjahdi, 29, said he was driving directly in front of Diana's Mercedes and had no doubts that the crash was an accident.
"I am absolutely convinced, clear and certain that this was a tragedy -- but it was an accident," he told the Daily Mail newspaper in January 2004. "Any conspiracy would have had to be carried out by invisible men."
Dame Stella Rimington, Britain's one-time spy chief, totally dismissed suggestions there had been a sinister plot.
"It was a car accident and that is that. Basically all conspiracy theories are mad," she said in a newspaper interview.
Following Stevens' report, preliminary inquest hearings will take place in early January under Elizabeth Butler-Sloss, a former senior judge who has stepped out of retirement to replace Burgess. An initial decision to hold them in private was overturned last week.
- REUTERS