With his avuncular smile, felt fedora and long, hand-kitted scarf, Robin Harper cut a distinctive figure when he won a seat at Holyrood in 1999.

The first elected Green parliamentarian in the United Kingdom, Mr Harper styled himself rather like Dr Who as played by Tom Baker in the 1970s but behind his eccentric appearance lay a fierce intellect.

Robin Harper was respected across the Scottish parliament – by Unionists and Nationalists, alike – as a thoughtful, constructive politician. And so effective was he at promoting his party’s message that, after the 2003 election, he was joined at Holyrood by six more Greens.

In the foreign country of 23 years ago, the Greens had no stated position on the constitution although it was no secret that Mr Harper favoured the maintenance of the United Kingdom (he would go on to vote No in 2014).

Instead of obsessing over independence or, indeed, any number of vogueish issues such as gender reform, the Greens focused on the environment.

A larger parliamentary presence demanded a more formal party structure and so, between 2004-08, Mr Harper served as co-leader, alongside Shiona Baird.

But, just as Tom Baker’s Dr Who regenerated to become Peter Davidson’s, so the leadership of the Scottish Greens was to change.

In 2008, the Glasgow MSP Patrick Harvie – who would serve alongside a series of female co-conveners – became the public face of the Scottish Greens.

And then things got very weird, very quickly.

Angry and radical, with an insatiable appetite for the limelight, Mr Harvie took his party into a new dimension.

He drove through a vote committing the Scottish Greens to independence and, his attention drifting from such matters as climate change, turned his party into the home of political trans activism.

As Scots prepare to vote in Thursday’s Scottish parliamentary election, there are new occupants of the Green Tardis.

Elected last September, co-conveners Ross Greer and Gillian Mackay are – if polls are to be believed – on track to be hugely influential in the parliament’s next session.

If SNP leader John Swinney falls short of a majority, it is to the Scottish Greens he will first turn for support in returning as First Minister.

All the signs are that the Greens are ready to strike a deal. And that should fill us with horror.

It is vanishingly unlikely that the SNP and the Greens will enter into another formal arrangement. The decision of former First Minister Humza Yousaf to end the Bute House Agreement, which had seen Greens Patrick Harvie and Lorna Slater serve as ministers, in 2024 hastened his political downfall. Lessons have been learned.

Instead, Mr Swinney is expected to offer the Greens concessions on their pet policies in return for their support in budget votes.

Mr Greer and Ms Mackay have quite the wishlist…

During this election campaign, we’ve heard crank idea after crank idea from Scottish Green candidates. There is, it seems, no policy proposal too stupid for the party to promote.

Take, for example, the call by Lothians candidate Kate Nevens for the abolition of prisons.

If Ms Nevens – who will become an MSP if the Greens do as well as their best polling suggests – had her way, almost 600 murderers would be released from jail.

Joining them on the streets would be the 200+ men imprisoned for rape or attempted rape and countless more locked up for crimes of violence.

In a video posted on social media site Instagram, Ms Nevens described herself as a prison ‘abolitionist’.

‘Prisons,’ she said, ‘are not safe, they’re violent, they’re poor for people’s health and wellbeing, particularly if you’re a woman. And they fail to support rehabilitation.

‘So actually they do not make those of us who are not breaking the law safer either.’

Countless police officers and victims of crime will, of course, point out that the removal of violent criminals from society makes those of us who don’t break the law considerably safer but Ms Nevens prefers we think of the perpetrators first.

Normally, when an election candidate comes out with something as bizarre as Ms Nevens’s call for the end of prisons, party leaders move swiftly into damage limitation mode, distancing themselves from whatever has been said.

With this in mind, the Scottish Greens’ response to their candidate’s remarks is instructive.

Rather than bringing the conversation back to a reality in which we can’t have dangerous criminals roaming free, co-convener Gillian Mackay said prisons would still be required in the ‘short term’ for the incarceration of violent offenders.

Those two words - ‘short term’ – tell us everything. Ms Nevens’s desire to close prisons isn’t some outlier view, it’s perfectly mainstream in the modern Scottish Greens.

Until the party has its way and all of Scotland’s most violent people are set free in the name of making us all safer, it is committed to making prison as dangerous as possible for women.

Former First Minister Nicola Sturgeon may have led the charge on attempting to remove women’s sex-based rights at the behest of crank trans activists but she would not have got so far as she did without the wildly enthusiastic support of the Greens.

It was an era that produced a greatest hits of gender insanity, including the claim from Maggie Chapman – all but certain to be re-elected as an MSP for North East Scotland next week – that it was impossible to define somebody’s sex without testing their chromosomes.

‘I’ve never had mine tested,’ she revealed. ‘I don’t know what mine are.’

Despite a UK Government block on Holyrood plans to allow anyone to declare themselves a member of the opposite sex and a Supreme Court ruling that, so far as the law is concerned, a woman is an adult human female, the Scottish Greens remain committed to reforming the Gender Recognition Act.

Not only do Mr Greer and Ms Mackay wish for a world in which biological males are free to invade women’s single-sex spaces such as refuges, changing rooms, and even prisons, they wish it to be known that anyone who does not subscribe to the outlandish creed of trans ideology is unwelcome in their party.

Interviewed last December they said someone’s failure to believe that a transwoman was a woman was a ‘red line’ issue when it came to membership.

So far as the Scottish Greens are concerned, until prisons are scrapped, dangerous males who declare themselves female – the rapist Adam Graham, who changed his name to Isla Bryson before his trial, for example – should be locked up alongside some of the most vulnerable women in society.

The Greens’ reckless and dangerous policy agenda – an unpalatable cocktail of post-modern gibberish, pie-in-the-sky wishful thinking, and cruel misogyny – is dressed up by its leaders as progressive, fair, and compassionate.

But, time and again, it seems the party adopts positions not because they make sense but because they are appropriately ‘revolutionary’. After his election as leader of the Green Party in England and Wales last September, Zack Polanski moved the party’s position on drugs from liberal to insane.

In power, Mr Polanski would legalise all drugs, including heroin, crack cocaine, and crystal meth, and then ‘regulate’ them. Doctors would be empowered to prescribe heroin and cocaine while powerful hallucinogens such as LSD would be sold in specially licensed premises.

But if your taste, instead, runs to powerful cannabis then Mr Polanski wishes to make life even more convenient by allowing it to be sold in local shops.

The Scottish Greens have now adopted the same positions as their sister party.

The party’s Holyrood election manifesto states that it wishes to ‘end the criminalisation of drug use and work towards a legal, regulated system of drug supply’.

Scotland may be in the grip of a drugs death crisis, with lethal overdoses running at far higher rates than anywhere else in the UK, and the Greens answer is to make it easier for addicts to get hold of the poisons that kill so many of them. But don’t fret. 

The Greens aren’t completely reckless when it comes to the drugs people consume. They may wish to make heroin easier to obtain but they have also announced plans to make it more difficult for ex-smokers to vape.

Next week’s election may be about the issues over which Holyrood has competence but the Scottish Greens, ever enthusiastic performers that they are, have devoted a substantial section of their manifesto to conflict in the Middle East.

Describing a ‘genocide’ in Palestine, the manifesto proposes a witch-hunt of anyone in Scotland ‘complicit in war crimes through their service with the Israeli occupation forces’. 

Given that every Israeli is conscripted, this would appear to mean the Greens would seek to criminalise anyone who’d done national service in their home country.

When it comes to Palestine, the Scottish Greens and Zack Polanski are rotten peas in a pod. No atrocity against Jews is too great for either to avoid downplaying it.

Despite the terrifying rise in incidents of anti-Semitism since the murderous Hamas invasion of Israel on October 7, 2023, Mr Polanski recently said there was ‘a conversation to be had about whether it’s a perception of unsafety or it’s actual unsafety’.

When ‘actual unsafety’ came in the shape of knife attacks on two Jewish men in London’s Golders Green on Wednesday, Mr Polanski shamed himself.

While other politicians joined in praise of the unarmed police officers who bravely tackled the suspect in the incident, Mr Polanksi shared on social media a post which read: ‘Essentially…officers were repeatedly and violently kicking a mentally ill man in the head when he was already incapacitated by Taser.’

In response, Metropolitan Police Commissioner Sir Mark Rowley wrote a magnificently withering letter to the politician in which he described his pride in the officers involved. He was ‘disappointed’ Mr Polanski had shared ‘inaccurate and misinformed commentary’.

On drugs and gender, particularly, says one former Scottish Green Party activist, the party exposes itself as ‘elitist and out of touch’.

‘I joined the Greens because it was the party of the environment. Now we’re the party of privileged lunatics. Nobody living in a deprived area where drugs are killing people thinks it should be easier to get drugs. Nobody.

‘And what the hell has the gender thing got to do with the environment? How did we get from being the main party for people who care about the planet to being the home for men who want to use women’s communal showers?

‘Here’s the thing. The Greens have always been pretty middle class but the party used to have a bit of self-awareness. Now, it’s just privileged professional politicians talking down to anyone who doesn’t think people can change sex.’

Back in 1999, Robin Harper represented a Green Party sure of its mission and ready to work with those from across the political spectrum in the name of fighting climate change.

Today, Mr Harper is a member of the Labour Party and the Scottish Greens, under Ross Greer and Gillian Mackay, are a collective of anti-Israel cranks and misogynists peddling a crackpot manifesto for chaos.

All of this would be irrelevant if the party was not so worryingly close to power.

But the terrible truth is that Ross Greer and Gillian Mackay stand to be among the most influential MSPs in the next Holyrood session.

If he falls short of a majority on Thursday and needs their support to continue as First Minister, John Swinney will ask the Scottish Greens which of their deranged ideas they’d like him to enact first.