Prince William is “tentatively” welcoming an independent investigation into the circumstances surrounding a BBC interview that his late mother Princess Diana took part in.

William called the probe “a step in the right direction.” He added that it “should help establish the truth behind the actions” that led to the interview as well as “subsequent decisions taken by those in the BBC at the time.”

The BBC has appointed a retired senior judge to lead a probe into the 1995 interview after her brother Charles Spencer renewed his accusations this month that journalist Martin Bashir used fake bank papers to force Diana into the interview. The papers appeared to show payments made to staff working with the royal family.

The investigation will look at the BBC and Bashir’s actions, whether the BBC was aware that the bank statements were “mocked up” and if the fake papers actually influenced Diana’s behavior.

In the 1995 interview, Diana said “there were three of us in this marriage” a reference to Charles’ affair with Camilla Parker-Bowles. It was watched by millions of people and sent shockwaves through the world.

Diana and Charles split in 1996. She died in a car crash in Paris in 1997 as they were pursued by paparazzi. Charles married Camilla in 2005.