Jane Scotchbrook, a retired detective superintendent with London’s Metropolitan Police who spent over two decades in the criminal investigation division, discussed her role in the Diana inquiry with Christine Lampard on British morning show Lorraine.

“My main role,” Scotchbrook said of the inquiry, which was named “Operation Paget” and looked at a number of conspiracy theories about the princess’ death, “was to speak to Diana, Princess of Wales’ confidants to try and find out one way or another—it is about following the evidence—whether she was pregnant, whether she was due to get married and whether she had any concerns for her safety.”

As part of the investigation Scotchbrook spoke to a number of close friends Diana had spoken to on the telephone in the last days of her life, including wife of the Brazilian Ambassador to Washington Lúcia Flecha de Lima and Daily Mail journalist Richard Kay.

None of those interviewed believed that Diana was either planning on becoming engaged to then-boyfriend Dodi Fayed or starting a family with him. Both of these claims have been publicly repeated by Fayed’s father, billionaire Harrods owner Mohamed Al-Fayed.

“We looked at absolutely everything,” Scotchbrook told Lampard, adding that she was “completely, completely satisfied that we came out with the right result.”

The results of Operation Paget were used in a formal inquest into the death of Diana held from 2007 to 2008.

The final ruling from this inquest found that the princess had been unlawfully killed as a result of the “grossly negligent driving” of paparazzi members who followed, at speed, Diana’s car as she was being driven from the Ritz hotel in Paris with Dodi Fayed and bodyguard Trevor Rees-Jones, by acting head of security at the Ritz, Henri Paul.

The judge also attributed partial responsibility for the accident to Paul, who was found to have exceeded the legal limit of alcohol consumption to drive.

The Mercedes car in which the group was traveling in excess of the speed limit lost control upon entering the Pont de l’Alma tunnel before colliding with a central reservation pillar. Fayed and Paul were pronounced dead at the scene of the accident. Diana was taken to the Pitié-Salpêtrière Hospital, where attempts to save her life were unsuccessful.

Bodyguard Rees-Jones was the sole survivor of the crash. None of the casualties were wearing seatbelts.

Despite the investigation’s findings, some still question the official outcome with conspiracy theories continuing to circulate, many of which were addressed in the recent Channel 4 docuseries Investigating Diana: Death in Paris.

Speaking on this subject, Scotchbrook said: “That is the thing with conspiracies, no one wants to believe maybe that this huge personality died as any one of us may do in a car crash.”

“There were so many elements to it,” she continued, “to get that staged, for so many people to be involved, if there had been a conspiracy for everyone to keep quiet about it—we’ve just done the best job possible just to prove [what really happened].”

“I think people will always wonder,” Scotchbrook ended, “because she was so large and no one likes the fact that she’s not here anymore.”

This year marks the 25th anniversary of Princess Diana’s death and to commemorate this a number of TV series, documentaries and biographies have been published celebrating the royal’s short life.

Though there are no official royal plans to mark the anniversary, both Princes William and Harry have paid separate tributes to their mother throughout the year, most recently with Harry referencing Diana’s relationship with Nelson Mandela in his keynote address at the United Nations in July.