You know you’re at the fag end of a government when the ruling party abandons the pretence of even trying.

It’s like when both parties in a marriage become reconciled to their inevitable divorce and are suddenly free to let rip about how they truly feel about each other.

There has long been an arrogance about the SNP leadership in power, but recent behaviour suggests a descent into open contempt for the voters who put it there.

The frustrating reversion to pedantry and legalese by the First Minister and former First Minister, in response to straightforward questions about whether they deleted Whatsapp messages during the Covid pandemic, is an example.

Humza Yousaf’s stubborn refusal to abandon the unpopular and divisive Gender Recognition Reform Bill, is another.

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But it is his tin-eared refusal to sack Heath Secretary Michael Matheson in response to public revulsion over the handling of his £11,000 mobile phone bill that is the tawdriest spectacle of this failing government.

Whether Mr Matheson clinging onto the job by his fingertips is more culpable than his boss’s patent lack of self-awareness in defending him, is disputable. I suppose you could argue that, at least, Mr Yousaf is showing loyalty.

Of more significance than the behaviour of either is what it says about the party and what it has become following 16 years of unbroken power.

The SNP took its first tentative steps in government as a minority administration in 2007, following more than 50 years of domination by its predecessor at Westminster and Holyrood.

The foot soldiers of what had become known as the Scottish Labour Mafia were the serried ranks of well-fed time servers who sat perched on the opposition benches throughout the 1980s and 1990s and the municipal bag carriers who cut their teeth in Labour heartland councils before being handed safe seats at the Scottish Parliament, following devolution.

By the mid-noughties voters - particularly those in deprived inner cities and deindustrialised communities - were tired and disillusioned at the party’s quadrennial promises that things would improve, only for nothing to change.

Scottish Labour was despatched from office and in came the charismatic Alex Salmond, who promised a break from the past and a new way of doing things, that would put the people of Scotland first.

In the beginning, there were some popular vote winners, including the scrapping of prescription charges - which signalled the party’s commitment to the founding principles of the NHS - free bus travel for young people and pensioners, and the freezing of council tax rates.

And, of course, there was the 2014 independence referendum, which narrowly failed, but which changed the narrative over Scotland’s place in the Union and convinced new constituencies of voters of the merits of it as a sovereign nation.

But populist giveaways, and commitment to a dream that now looks more distant than ever, were not enough to paper over the cracks.

A scandal over the party’s internal finances earlier this year, and the degrading spectacle of police tents erected outside the home of Nicola Sturgeon, signalled to many people that, seduced by the narcotic of power, the SNP had become that which it replaced.

Where once we had the Scottish Labour Mafia, we now have the Scotia Nostra, for whom mutual back-scratching and self-interest appears to be more important than governing.

No-one exemplifies the boys’ club culture more than Mr Matheson, who has been in it from the start. Part of the disillusionment with the early days of devolution was that voters were promised a new type of politics and a new breed of politician.

They expected people who could bring the benefits of a life outside of politics: experts and specialists, people who had run their own businesses or large organisations, former members of the armed services, senior medics, and members of the clergy. Instead, we got councillors, party researchers and local constituency apparatchiks.

The Herald: What is Alex Salmond's motivation?What is Alex Salmond's motivation? (Image: PA)

No-one screams greasy pole like Mr Matheson, who worked as an occupational therapist in local government before collecting his first MSP’s pay cheque in 1999. For someone routinely described as among the most able of SNP ministers, it took him 12 years to become a member of the Government, appointed as a junior minister for public health in May 2011.

Since then, he has risen without trace, with Cabinet jobs in Justice; Net Zero, Energy and Transport; and NHS Recovery, Health, and Social Care.

Prior to the scandal over his mobile phone bill, you could spend all day showing a picture of him to people on Buchanan Street or Princes Street and be lucky to find a single one able to recognise him.

Ability in this SNP administration appears to be defined by a Macavity-like talent for never being caught holding the smoking gun. When, in 2018, the Scottish justice system faced turmoil, with high-ranking officials accused of misconduct, including bullying allegations against Police Scotland Chief Constable Phil Gormley, leading to resignations and claims of chaos, Mr Matheson was criticised for being "invisible" and accused of "closing down questions" amid allegations of gross misconduct.

What important causes has he ever been aligned with; what bills has he championed; on what important issues has he led from the front? Mr Yousaf’s loyalty might appear commendable if anything meaningful could be cited in response to those questions.

As it is, it looks more like support for a chum who is in danger of losing his seat at the election, and whose final-salary pension would be boosted significantly were he to leave politics as a minister rather than simply an MSP.

The scandal, and Mr Matheson’s grim determination to brazen it out throughout weeks of bad press for the government he serves, reveal not only a lack of decency and self-respect but more damagingly, a glaring lack of competence.

I’m sure he would be the first to admit he’s not known for grand vision or soaring rhetoric. He’s a nuts and bolts man, the plodder’s plodder. If you’re looking for someone to parse a sub-clause in a statutory instrument, he’s your man.

And that makes his failure to ensure he was using the correct SIM card in his mobile phone when travelling abroad so baffling. As is his insistence that, as a follower of football, he didn’t watch the Celtic v Rangers match on TV, alongside his sons, which we are led to believe ran up the eye-watering roaming data charges.

Even if, as he claims, he is not a Celtic fan, it stretches credulity that while the rest of his family were watching one of the showpiece matches of the season, he was somewhere else, perhaps outside widget-spotting or counting drainage stanks.

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Perhaps he is hoping to sit it out long enough for the next instalment of the SNP’s fall from grace to start dominating the news agenda, with Mr Salmond’s forthcoming legal action against the Scottish Government.

Among those accused of "misfeasance" is his former protégé and ally Nicola Sturgeon, raising the distinct possibility of the pair facing off against one another in court.

The former SNP leader - who now heads the breakaway Alba party - has already been awarded £512,000 over the Scottish Government’s mishandling of harassment complaints against him and he was subsequently cleared of sexual assault charges in a separate criminal trial in 2020.

So, one wonders what his motivation might be in provoking a high-profile civil case, where much of his admittedly sleazy behaviour towards women will be aired in public, doubtless leading to lurid newspaper headlines at a time when his former SNP colleagues will be scrapping for every vote they can muster.

A messy divorce benefits no-one and inevitably it is the family and friends of the warring couple who suffer most. Perhaps, in their respective circumstances, Mr Yousaf and Mr Salmond should put personal considerations aside and think of the voters.

Carlos Alba ran the media campaign for Ken MacIntosh’s bid to become Scottish Labour leader against Kezia Dugdale