Princess Diana death revolves around unresolved conspiracy theories.
While some believed it to be a murder, others conjectured Diana's last day came as a mere accident.
Official investigator Eric Gigou, of the Brigade Criminelle from France, however, tells Channel 4 documentary that all these theories are “far-fetched", except for one, that deeply disturbs him till date.
He said: “The Brigade Criminelle is a special unit charged with handling complex cases.
“We’re not going to lower ourselves to dismantling conspiracy theories each more far-fetched than the other.
“All to satisfy the rather misplaced curiosity of a certain part of the public.”
But, Mr Gigou added: “In my mind, the only door that remains open is the testimony of the driver of the Fiat Uno.”
Fabrice Cuvillier, also of the Brigade Criminelle, added: “This Fiat Uno exists, that’s for sure. It’s not a hallucination. It’s not some fantasy.
“It’s not something we threw out to create a diversion. It exits.
“We didn’t find this Fiat. But it would be dishonest of me to look you in the eye and say: ‘We didn’t let the Fiat slip through.’
“I don’t think so, but I’m not 100 percent sure.”
Brigade Criminelle chief Martine Monteil said she has “always been frustrated by this Fiat Uno because I like a well-finished business.
“It’s out there for sure. Unfortunately, we don’t have it. But you know, the driver of the Fiat Uno, he’s not the real culprit.
“He’s driving along quietly and then a Mercedes arrives at high speed and bumps into him.
She concluded: “The responsibility remains with the Mercedes.”
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