OF all the murky dimensions of last week’s big media scandal – and the gloom is luminous – one aspect must have been particularly baffling for viewers in Scotland.

When pundit lawyers were pulled into newsrooms to explain why The Sun and the BBC weren’t naming the high-profile presenter at the heart of this – “top BBC star in sex pics probe”, The Sun’s front page read – they generally gave two different explanations.

First, they cited the law of defamation. If you connect me with a story which will seriously damage my reputation – and you can’t prove your allegations are true or substantially true – then you’ve exposed yourself to the mother of all defamation suits.

Substantial damages and ruinous legal costs can follow, as several idiots seem likely to discover having taken to ­Twitter, Inspector Clouseauing their way into ­connecting the wrong BBC big-name with the tabloid’s claims.

But media lawyers also highlighted a ­second reason for keeping schtum about the presenter’s identity: privacy law. If you are being investigated for a criminal offence – and until you’ve been formally charged – the law now says you have a ­“reasonable expectation of privacy” and should not be named in connection with the ­investigation.

READ MORE: Drugs policy is broken, but does Scotland have the power to change it?

Unless, that is, you are Nicola ­Sturgeon, Peter Murrell (below) or Colin Beattie, in which case you can expect to be instantly ­identified with an ongoing police inquiry, accompanied by wall-to-wall coverage and days of reporters camped outside your ­family home.

When Police Scotland issued press ­releases confirming that “a 52-year-old woman” and a “58-year-old man” had been arrested in connection with the ongoing ­investigation into the SNP’s finances, ­Peter Murrell and the former first minister were immediately identified across the media as the individuals in custody, notwithstanding the fact they had not been charged, and no charges have followed – so far.

People are entitled to be confused by these glaring discrepancies. Ironically, we have the BBC to thank for these developments in privacy law. It was Gary Smith – now BBC Scotland’s head of news and current affairs – who despatched the ­helicopter to take live aerial shots of Sir Cliff Richards’ estate being raided by South Yorkshire Police during the height of ­operations Yewtree and Midland in 2014.

The National: Nicola Sturgeon and Peter Murrell

Despite this shock-and-awe reporting, the geriatric crooner was never arrested or charged. Richards sued the BBC and the police force for breaching his privacy. At the time, the BBC argued there was an overriding public interest in ­disclosing Richards’s identity as the subject of the ­inquiry. But in court, it didn’t wash.

The old press adage says that a picture tells a thousand words. Courts think so too. In one of the earliest privacy cases in the UK, Naomi Campbell sued the Daily Mirror. The red-top had revealed that – contrary to Campbell’s public claims that she never touched class A drugs, unlike some of her coke-addled ­contemporaries – the supermodel had not only used drugs, but was attending Narcotics Anonymous meetings. The tabloid didn’t just share these revelations. The Mirror also decided to print a long-lens photograph of Campbell leaving one of these suddenly-not-so-anonymous meetings. She sued, ­alleging breach of privacy.

The courts held that while the Mirror was entitled to correct the record about Campbell’s substance abuse, sharing the covert photo invaded her privacy, going far beyond any necessary intrusion into her private life that the public interest might justify.

The damages Campbell won were ­tokenistic – just £2500 in 2004 – but the case marked the beginning in the rise of privacy suits against Britain’s ­feral press, as public figures, their ­lawyers and associated reputation management ­professionals tried to reassert some ­control over the aspects of their clients’ private lives which could be reported (without an intimacy fee being levied).

Cliff Richards’s case built on this judge-made law. In 2018, he took £210,000 off the BBC for its off-the-scale reporting of the police raid, and set in train a series of cases culminating in the UK Supreme Court’s judgment in ZXC v Bloomberg last year.

ZXC – as we’re obliged to call him – is an American-born businessman who was subject to a criminal investigation in the UK. As part of that investigation, contact was made with a foreign government’s law enforcement agency. Financial ­journalists at Bloomberg got hold of this request for information, and reported that it had been made as part of the criminal inquiry.

READ MORE: Andrew Tickell: UK boycott laws and Glasgow’s Nelson Mandela Place

ZXC sued, claiming this report infringed his privacy, demanding the article should be taken down. Bloomberg said no.

Its arguments were simple: the story was true. There was a lively ­public ­interest, it said, in disclosing that a prominent public figure was under ­active ­investigation by the authorities for ­alleged financial irregularities. In law, people ­accused of crime benefit from the ­presumption of innocence, and the public should be assumed to give them the ­benefit of that doubt. Someone on whom official suspicion falls might never be charged – never mind prosecuted or convicted of a crime. There can be smoke without fire, Bloomberg argued. Mud doesn’t always stick.

But in 2022, the UK Supreme Court ­disagreed – confirming that “a person ­under criminal investigation has, prior to being charged, a reasonable expectation of privacy”. Why? Because, the justices said, “reputational and other harm will ordinarily be caused to the individual by the publication of such information. The degree of that harm depends on the factual circumstances, but experience shows that it can be profound and irremediable.”

It didn’t matter that Bloomberg’s ­report was true. It didn’t matter either that Bloomberg faithfully reported the letter journalists there got their hands on. For the courts, ZXC had a “reasonable expectation of privacy” until the authorities formally pointed the finger at him and charged him with a crime.

They never did. Bloomberg was ordered to pay out £25,000 in damages – and not to republish the information.

These legal developments have not been uncontroversial. Critics of the judgment suggested “UK judges are helping the next Robert Maxwell”, claiming that “powerful people under investigation for criminal activity have just been given a path to keep their names off print”. Has privacy law gone too far?

Rebalancing the relationship between privacy and free expression has fallen in and out of the UK Government’s priorities. This isn’t just a right-wing preoccupation. Private Eye editor Ian Hislop has recently explained that the golden years of fending off menacing defamation writs have now been replaced with lawyers’ letters alleging the magazine has misused the private data of people who feature in its pages. It’s a new legal basis, but an old strategy for repressing legitimate scrutiny.

The impact is felt here too. Talk to ­Scottish journalists, and many will be able to give you examples of people – senior people still active in public life in this country – who have been arrested and questioned on suspicion of committing serious offences, but not charged. ZXC means this fact has never reached the public domain, and perhaps never will.

The ZXC judgment is why some press outlets – the BBC most prominently – ­refused to cover reports that Tory peer ­Michelle Mone’s business interests were being probed by the National Crime Agency.

PPE Medpro secured more than £200 million from the UK Government during the early stages of the pandemic without tender. Mone’s London home was raided last year in connection with this NCA investigation – a story which, as one observer quipped, was suddenly “everywhere except BBC News”. A case of once burned, twice shy, perhaps.

But reflecting on the gusto which characterised the Sturgeon raid, it isn’t so ­simple, is it?

If broadcasters and publishers can choose when to push the limits, why aren’t they pushing them in a consistent way? Surely the public interest favours ­disclosure of all of these police ­investigations, or none of them?