King Charles’s son was part of a group of household names, also including Sir Elton John, Baroness Doreen Lawrence, Liz Hurley and Sadie Frost, who alleged that acts including voicemail interception, landline tapping and obtaining information by deception – known as “blagging” – were carried out by private investigators, freelance journalists and staff at ANL. ANL denied the claims as it defended the cases, which it also said had been brought too late. Mr Justice Nicklin said that none of the seven had proved the allegations of unlawful information gathering.

In a joint statement after the judgment, Harry and Baroness Lawrence said: “It is a complete and obvious whitewash, but sadly not altogether unexpected.”

They said: “We came to court seeking justice and accountability. But we have received neither. Generic findings about various private investigators that were held by the courts in these parallel claims to have carried out unlawful activity at the very same time in relation to similar stories and well-known individuals have been wholly ignored.

“The fact that this court has chosen to dismiss them represents an inconsistency which is hard to understand or reconcile with common sense, or the evidence heard in the court room itself. It is a complete and obvious whitewash, but sadly not altogether unexpected.

“However, the lengths to which the court has gone to exonerate the Mail is as shocking as it is totally unwarranted. When the court says there is not sufficient evidence of wrongdoing, despite the documents showing otherwise, then one does wonder how justice was ever going to be achieved.”

Harry’s statement has been criticised by two former justice secretaries – Alex Chalk KC, who served under Rishi Sunak, and Sir Robert Buckland KC, who served under Boris Johnson.

Mr Chalk said, as per The Telegraph: “Expressing disagreement with a judgment is perfectly reasonable. But Harry’s attack on a High Court judge was over the top, personal and unacceptable.

“Judges act in the name of the King and swear an oath of allegiance to the sovereign. That’s how our constitution works, as Harry should know better than most. However disappointed he was with the result, insulting one of HM’s judges is a line he shouldn’t have crossed.”

Sir Robert said: “The tone and content of the attack was not appropriate.”

He said that the Duke could instead have issued a statement saying: “The Prince is deeply disappointed by the court’s decision and will be taking advice as to his options in light of this. He will make no further comment.”