Former Scottish Green party stalwart Robin Harper's decision to vote Labour is a recognition of a straightforward truth – Brian Wilson

The Scottish Parliament’s D’Hondt system of proportional representation is open to abuse in which the dominant force in constituencies adopts a surrogate party to attract ‘list' votes

It has long been an enigma peculiar to Scotland. Why, in order to be “Green” with a capital G, was it also necessary to support independence and subscribe to a range of woke causes that have nothing to do with the environment? One would have thought any movement which truly prioritises the battle against climate change above all others would be in the business of maximising its support base. Instead, the Scottish Greens narrow it by placing all sorts of box-ticks in the way of persuadable voters.

Now Robin Harper, who was a good advertisement for what proportional representation brought to Holyrood in terms of political diversity, has called out his successors in spectacular fashion, accusing them of having “lost the plot” and suggesting they should “should listen as much as they shout”. It is an overdue case of the emperor’s clothes with Mr Patrick Harvie cast in that unlikely role. Along with his soulmate in government, Ms Lorna Slater, they have perpetrated a rather large con-trick upon the Scottish electorate under Green cover but with no environmental benefits to show for it – only chaos and disrepute.

There is not an environmental cause, from marine protection to domestic heating via recycling, on which they have failed to alienate people who want to do their best for the environment but do not equate that obligation with accepting top-down diktats imposed without reason or consultation. Those most entitled to be offended by this performance are the people who believe that a genuinely “Green” element at Holyrood would be an asset, as crusaders for relevant causes. Instead, they have become a fringe freak show identified with arrogance unmatched by competence.

The Green tag has been captured for other ends, particularly on the constitution. Genuine environmentalists who think breaking up the UK would be a thoroughly bad idea, not least for the environment, have been left without a home over the past decade. More than half the Scottish electorate are precluded from voting Green unless prepared to be counted as part of a “pro-independence” coalition.

The true standing of the Harvie-Slater Greens is borne out by election results. When the first-past-the-post system applies, support is so derisory they scarcely bother to stand. It will be interesting to see if they contest the Rutherglen by-election. However, the picture changes when the “list” system comes into play and that is key to the con for which the Scottish Greens have settled.

I always opposed the “D’Hondt” version of PR which Holyrood’s founding fathers adopted because it creates two classes of MSPs – constituency and “regional list”. Multi-member constituencies (as used in local government and in Ireland) would be a far better form of PR with all MSPs having equal standing in practice as well as theory.

The D’Hondt system is also open to potential abuse which arises when the dominant force in constituencies adopts a surrogate party to attract “list” votes which it does not itself require to return regional MSPs. That is the alliance of convenience which Nicola Sturgeon and the Scottish Greens embraced with enthusiasm and to mutual short-term advantage.

There was nothing new about the idea. In the early days, there were some in Labour circles who wanted to run “Co-operative” list candidates to mop up surplus Labour votes. Donald Dewar trampled firmly on that idea because he believed (rightly) that it would be an abuse of the system. He also saw the longer-term dangers.

As the pendulum swung and SNP hegemony emerged with a narrow majority, Ms Sturgeon showed no such inhibition, once the Greens had become a pro-independence party in the run-up to the 2014 referendum. Come into my parlour, said the spider to a more than willing fly.

In the last Holyrood election, SNP voters were encouraged to give their “list” votes to the Greens. It must be dawning on even the dimmest SNP tribunes that this was not a great idea in terms of electoral appeal as one policy after another unravels, while those alert to political survival might notice that the “second vote to the Greens” strategy can just as easily become a iiability.

If opinion polls stay where they are, the SNP will be pleading with supporters not to give “list” votes to the Greens because they, themselves, will need them to have a hope of retaining power. Gaming electoral systems backfires on the swing of a few percentage points and is more difficult to reverse than to encourage in the first place.

Possible electoral downsides are merely products of a cynical deal which has given entirely disproportionate influence to a political fringe. If it was being used to endorse policies which command general support, then fair enough. However, the Scottish Green ministers act in accordance with a reality – that their roles do not depend on public support but on SNP patronage.

Robin Harper referred to the Scottish Greens’ public image having been “damaged by failure to co-operate meaningfully with other interests, including the Westminster government”. There are many areas, the deposit return scheme being the obvious example, on which co-operation made sense and setting up conflicts none at all.

As a person with left-of-centre views who does not want to break up the UK, Mr Harper says he will vote Labour at the coming election. That is in recognition of a straightforward truth – to secure political change and progress, for the environment and much else, at Holyrood and Westminster, there is only one viable alternative.

The Scottish Greens can’t believe their luck that “shouting not listening” proved so productive for a few of them, if not for the environment. They are now as bad an advert for PR at Holyrood as Mr Harper was a good one and should be judged accordingly.