THE price of being outside party politics is not having a say. For the most part, I am entirely contented. But it can, occasionally, be frustrating. One such occasion was last week, when the Scottish Parliament had its vote for First Minister. There were two options on the ballot paper: Nicola Sturgeon, the most popular political leader of any party across the UK, or Willie Rennie, famous for being interviewed in front of amorous pigs. The Greens abstained.

Now, of course the Greens have every right to decide strategy, tactics and how to vote themselves. It is up to them – through whatever democratic channels they have. But when I heard they had abstained, I was genuinely perplexed.

I suppose that’s where the advantage of being outside party politics comes in. It was immediately obvious to me that whatever bubble this decision was taken in, it wasn’t one that included the broad, pluralistic mass of the independence movement.

Patrick Harvie’s explanation was that the SNP government should have sat down with them, as they had done in 2007, to agree some terms of enabling SNP minority government. Presumably the SNP, with 63 seats as opposed to the 47 they won in 2007 with Alex Salmond as leader, didn’t feel the need. I can only accept Patrick’s explanation at face value. But if that was what the Greens wanted, they went about in a strange way. Maggie Chapman announced immediately on May 6 that there was “no appetite” for a coalition and cited numerous “significant differences” – maybe not the best way to bring the SNP to the table.

Maybe the Greens were justified in taking the position they did. But what does abstaining on the vote for First Minister actually achieve? 2007 was pre-referendum. So much has changed since then. Not least that we are still pushing towards majority support for independence. Nicola was the only credible candidate. She was going to win anyway.

No doubt the SNP could and should listen more to the broader Yes movement. Maybe the Greens wanted to show they had some muscle that they were prepared to use. But everyone knows the SNP are two MSPs short of a majority and the Greens have six. We can count.

Not voting for Nicola Sturgeon, the woman who, for hundreds of thousands of people, embodies the inspiration of the Yes movement, looked petty. And it makes the job of persuading the huge, powerful SNP that they don’t have all the answers to the question of how to win independence that wee bit harder, in my opinion.

Surely the Greens would be more likely to win respect, and concessions, from the position of being a critical but friendly pro-independence ally?

If it was a vote in principle – that the Greens couldn’t vote for a woman whose politics they fundamentally disagreed with – it would be understandable. But the test of whether it was a vote in principle would have been if there had been another candidate who might have got elected. What if there had been the political will, and the numbers, to bring together a coalition around Kezia Dugdale for First Minister – would the Greens have abstained then?

Contrary to some arguments I saw on Twitter, voting for Nicola as the First Minister would not have bound the Greens to the SNP’s whole programme for government. Otherwise there would be no point in MSPs sitting in committees and voting on bills line by line and point by point every week.

Since the vote for First Minister, Nicola has shown that she is more inclined to lean left than right. No doubt not left enough for some, but appointing Jeane Freeman as Social Security Minister is quite a strong statement of intention. And I wonder if, with hindsight, the Greens believe there was sufficient justification for withholding support from Nicola.

I am glad that the Greens are in there and that the SNP will not have everything their own way. I want to see the Greens use their intellect, influence and muscle to improve government policy on things like council tax, land reform and redistribution of wealth. People will notice if the Greens use their voting power to extract practical achievements. Abstaining on the vote for First Minister just made them look more concerned with their own importance.

So, was it just a statement of, “See us, see what we can do, don’t take us for granted” – or is there something deeper going on?

There is some evidence from local counts that the Greens were winning transfers from pro-Union parties. We know that, try as they valiantly do to appeal to working-class voters, their vote mostly comes from the progressive middle classes. This is why they do better in Edinburgh than they do in Glasgow. We also know that more affluent voters tended towards being anti-independence – which definitely represents a wee bit of a conundrum for the Greens.

It’s not that I think the Greens should exclusively target a pro-independence vote. It is a good thing that they are still attracting people who voted No – it’s encouraging to everyone who wants to reach out beyond the converted.

But is there a conscious calculation to create greater distance between the Greens and the party whose raison d’être is independence for electoral advantage?

I hope not. The Greens have played a critical role in persuading people to the cause of independence. The constituency they appeal to will need to be won over to that cause. The election has dealt the Greens some strong cards to play with. They will no doubt use them to achieve some of their own policies – and good luck to them. But I also hope they use them in the overall interests of the independence movement.

As Kenny Rogers sang in The Gambler, “You gotta know when to hold 'em, know when to fold ‘em”.