It is not just the Mirror Group whose reputation is tarnished by the Prince Harry hacking ruling

The Independent was founded on the belief that journalism is a noble calling. It is a tragedy therefore when it is poisoned by cheating, criminality and a refusal to admit wrongdoing.

The findings of the High Court that the publisher of the Daily Mirror unlawfully hacked Prince Harry’s phone could not be more damning. It has been reported as a “partial” victory because the court did not find in Harry’s favour in all 33 cases, but the principle of good journalism is binary: either the Mirror cheated, and broke the law without a public interest defence, or it did not. Mr Justice Fancourt found that it did. Not only that, but its journalists and executives destroyed evidence and obfuscated about what they had done.

This poisons the well of journalism as much as it dents the reputation of a great brand. It is not just the Daily Mirror that is tarnished by these rulings. News UK, publisher of The Sun and the now defunct News of the World, has just settled out of court with Chris Huhne, the former Liberal Democrat MP. Other cases, including some against other newspapers, are pending.

So today’s rulings are a total vindication for those who claimed that many tabloid newspapers used criminal methods to secure what was mostly celebrity gossip and tittle-tattle – and was sometimes used for the darker purposes of seeking to intimidate those who would hold them to account.

It has been a long and difficult struggle for a large number of litigants, but Harry had more to lose than most. He has been a figure of ridicule for many reasons, but on this issue he has fought the good fight for the principle of decent journalism and accountability. Wise heads called him foolhardy when they should have saluted his courage. At least they can now accept that he has been vindicated.

Some of them may continue to play down the significance of what the High Court has decided. It may be said that journalism never had much of a reputation anyway, and that people will continue, rightly, to hold a low opinion of it.

We disagree. Journalism has always been a mixture of high principle and low entertainment. It is, as the late Alan Watkins called it, a “rough old trade”. But it is a precious trade. All tyrannies curtail the media, which makes it all the sadder and more reprehensible when journalists in free democracies pollute the media themselves.

Vladimir Putin would like nothing more than that public opinion in democratic countries should regard all journalists with contempt as the purveyors of untruths. The British public is properly sceptical of the tabloid press and its online equivalents, but we believe that good journalism is still recognised and valued.

The Duke of Sussex may be an unlikely ally in the permanent struggle to defend the integrity of journalism, but it matters that the reputation of the media be lifted as far as possible from the gutter.

Through David Sherborne, his lawyer, Harry called on the Metropolitan Police and prosecuting authorities to “investigate bringing charges against the company and those who broke the law”. He is quite right. Those who are guilty of these underhand and illegal practices must pay the price. The Murdoch empire is thought to have paid around £1bn to settle phone-hacking claims against it. Other companies, and the people who ran them and worked for them, are guilty too. It is important for the health of our democracy that they should not get away with it.

It has come to something when The Independent congratulates the younger son of a hereditary monarch for his services to democracy, but Prince Harry should be thanked for his perseverance in holding the noble trade of journalism to account.