Investigator Calls Princess Diana's Death a 'Terrible, Tragic Accident' in First-Ever TV Interview

Jayne Fincher/Princess Diana Archive/Getty Princess Diana

Twenty-five years after Princess Diana's death in a Paris car crash, an investigator on the case is speaking out about the incident.

In his first TV interview, senior police officer David Douglas appeared on ITV's Good Morning Britain Friday to talk about his findings surrounding August 31, 1997, when a car accident killed Princess Diana, her romantic companion Dodi Fayed and driver Henri Paul. Their bodyguard, Trevor Rees-Jones, was injured but survived.

"It's my absolute total belief it was a terrible, tragic accident in which three people lost their lives and one other person had their life turned upside down," Douglas said.

Host Ranvir Singh asked if it was the combination of no seatbelts, paparazzi chasing the car and the driver having some drinks.

"When you look at most incidents, accidents, you find there's a chain of events, and if any one of those chain of events had been different, it might not have led to that happening," Douglas said. "For example, if they'd been wearing seatbelts, our experts tells us it was probably an 80% chance that they would have survived the accident."

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Operation Paget, the investigation into the various conspiracy theories surrounding Diana's death launched by the British Metropolitan Police in 2004, was published online in 2006 for anyone to read.

"In the very beginning, Lord Stevens said that we're going to be as open and transparent as we could be," Douglas said, adding that he "stands by every word" in the report.

Prince Charles was interviewed as part of the investigation about a note that Princess Diana wrote to her butler in 1995 which said, "My husband is planning 'an accident' in my car, brake failure and serious head injury."

Scott Barbour/Getty David Douglas and Lord Stevens in 2006

Douglas said of interviewing Prince Charles, "So it's remarkable… but in actual fact, it was also unremarkable because it was a straightforward witness statement from someone who happened to be the Prince of Wales."

"When we went in — I'd never met him before obviously — I found him charming," Douglas said. "He was very polite, friendly. And we sat down — Lord Stevens, Prince of Wales, his private secretary, who was there also. So Michael, Pete, and myself, just the four of us in the room. Lord Stevens obviously took the lead and talked to Prince Charles about that note and what became obvious was that Prince Charles knew nothing about that note until it became public in 2003. He knew no more than we did."

Tim Graham Photo Library via Getty Prince Charles and Princess Diana

Princess Diana's note was written around the time she did her famous BBC Panorama interview with Martin Bashir.

An inquiry conducted last year by former supreme court judge John Dyson found that Bashir used "deceitful methods" to secure the interview by commissioning fake bank statements.

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Liba Taylor/CORBIS/Corbis via Getty Flowers outside Kensington Palace after Princess Diana's death

Lord Stevens regretted that he and his officers did not interview Bashir.

"If there'd been an allegation then that Bashir had produced allegedly fake documents to Princess Diana, which is a criminal offense, we'd have investigated it. My goodness me, we would have done," Stevens told the Daily Mail. "But this has only come out recently, which is unfortunate."