The Duke of Cambridge criticised the BBC for its failings which he says exacerbated her ‘fear, paranoia and isolation’.
He called for the interview to never be shown on TV again and said his mother’s interview with Martin Bashir contributed to ‘making my parents’ relationship worse’.
Meanwhile, in a separate statement the Duke of Sussex said: ‘The ripple effect of a culture of exploitation and unethical practices ultimately took her life.’
An inquiry found the BBC covered up ‘deceitful behaviour’ used by journalist Martin Bashir to secure his world exclusive interview with Diana, and ‘fell short of high standards of integrity and transparency’.
The journalist was in ‘serious breach’ of the BBC’s producer guidelines when he faked bank statements and showed them to Earl Spencer to gain access to the princess in 1995, a report by Lord Dyson said.
William said he was left with ‘indescribable sadness’ to know the corporation’s shortcomings had ‘contributed significantly’ to Diana, Princess of Wales’ state of mind in the final years of her life.
‘She was failed not just by a rogue reporter, but by leaders at the BBC who looked the other way rather than asking the tough questions,’ the duke said.
He said the BBC’s failings had not only let his mother and family down but the public as well.
The BBC has now written to the royal family to apologise for the circumstances surrounding the interview – in which Diana said: ‘Well, there were three of us in this marriage, so it was a bit crowded’, a reference to Camilla Parker Bowles – who Charles later married.
Personal expressions of regret have been sent to the Queen, Prince of Wales, the dukes of Cambridge and Sussex, and Diana’s brother Earl Spencer.
The earl has said he ‘draws a line’ between the Panorama interview with his sister Diana, Princess of Wales and her death two years later.
William said in his statement: ‘The interview was a major contribution to making my parents’ relationship worse and has since hurt countless others.
‘It brings indescribable sadness to know that the BBC’s failures contributed significantly to her fear, paranoia and isolation that I remember from those final years with her.
‘But what saddens me most, is that if the BBC had properly investigated the complaints and concerns first raised in 1995, my mother would have known that she had been deceived.’
He ended with the words: ‘In an era of fake news, public service broadcasting and a free press have never been more important. These failings, identified by investigative journalists, not only let my mother down, and my family down; they let the public down too.’
Harry praised Diana in his own statement, saying: ‘Our mother was an incredible woman who dedicated her life to service. She was resilient, brave, and unquestionably honest.
‘The ripple effect of a culture of exploitation and unethical practices ultimately took her life.
‘To those who have taken some form of accountability, thank you for owning it. That is the first step towards justice and truth. Yet what deeply concerns me is that practices like these – and even worse – are still widespread today.
‘Then, and now, it’s bigger than one outlet, one network, or one publication.
‘Our mother lost her life because of this, and nothing has changed. By protecting her legacy, we protect everyone, and uphold the dignity with which she lived her life. Let’s remember who she was and what she stood for.’
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