It is difficult to know which would be worse - that the Scottish National Investment Bank blew £9 million on the Deposit Return Scheme because it was leaned on politically or on the basis of its own diligence.

Either way, it does not say a lot for the credibility of an organisation that has not yet amassed much of that commodity. Of all Scotland’s economic needs, a helping hand for a doomed SNP/Green project would not feature high on most people’s priority list.

Sure, they may point out, £9 million is chickenfeed in the world of public finance and is even dwarfed by the £65 million which the waste contractor, Biffa, was binned for when administrators moved into Circularity Scotland, the scheme’s administrator. There are lots of smaller creditors as well – victims of a project driven by political conceit and pressed on with in the face of abundant evidence of where it was heading. The fact ministers responsible for this folly are still in place (with the welcome exception of Nicola Sturgeon) compounds a scandal that has a long way to run.

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Circularity Scotland always struck me as a very odd client for the SNIB to have alighted upon. Plenty Scottish businesses would have appreciated a £9 million loan in May 2022 to help them through hard times, with higher claims to public support than one with the sole purpose of facilitating a project which already carried the kiss of death.

When he gave evidence to the Economy and Fair Work Committee of the Scottish Parliament on 21st June, the bank’s chairman, Willie Watt, was repeatedly asked about ministerial involvement in the decision to offer the £9 million to Circularity Scotland. Mr Watt was adamant that there had been none.

The convener, Claire Baker MSP, put the question in slightly different form: “Would you say that there was an expectation from the Scottish Government? When the loan was announced, there was quite a nice picture and press release that went out that included the minister, yourselves, RBS and Circularity Scotland, and it looked very much like a joint venture”.

Mr Watt was indignant: “It honestly was not. We make all our decisions totally independent of the Scottish Government. We are a fiercely independent institution”. Aye, right. Mr Watt waxed on: “There was no Government involvement [though] clearly, we were aware of the support that the Scottish Government was giving to the scheme”.

Indeed they were. As now known from a Freedom of Information request, no less a personage than the First Minister, Nicola Sturgeon, wrote to Circularity Scotland a letter of support which they duly passed on to the Scottish National Investment Bank with the message: “We thought it would be helpful to share with you and the team this letter received from the first minister reiterating the Scottish Government’s support of CSL to deliver the DRS in 2023.” That’s circularity at work.

In the face of such entreaties, what is a state banker to do - even if the birds in the trees could work out what was happening? In December 2021, there had been an announcement of further delay until August 2023 to the fatally misconceived scheme. Circularity Scotland needed cash to keep it going. All this, bear in mind, before the Single Market Act featured in the narrative subsequently concocted by Humza Yousaf, Lorna Slater et al.

Colin Smyth MSP reminded Mr Watt that, by the time of the photo-opportunity “there were numerous internal reports flagging up concerns about the scheme and there was widespread opposition from many potential customers. It does not say a lot about your due diligence process that, given all that, you thought in May 2022 that it was a good investment”.

Mr Watt replied: “The delays to the scheme were not helpful but the company was clear that the scheme would be viable. The big picture is that many countries have implemented deposit return schemes successfully. We felt that Circularity Scotland could do the same here.” I suppose this explains why bankers rarely trust their “feelings” rather than inconvenient evidence.

But what of these “many countries”? We are often advised to look to Ireland, which makes it surprising that the comparator of our neighbours failed to feature in Ms Slater’s histrionics about how the Scottish scheme’s failures were due to evil machinations from Westminster rather than her own determination to pick a fight, come what may.

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By happy coincidence, the Bank of Ireland has just emerged as financial sponsor for Re-turn, the Irish Government’s scheme which, having kicked off long after Scotland’s, is due to go live next February. Lo and behold, Ms Slater, it does not include glass - the crucial aspect on which no compromise was permitted in Scotland.

In Ireland as here, there is already a recycling rate for glass of more than 80 per cent so the Irish Government took the sensible decision to walk before running and thereby actually achieve something. Its immediate imperative is to meet the EU directive requiring 77%  of single-use plastic bottles to be collected by 2025, rising to 90% by 2029.

Would EU guidance, which we are normally instructed to revere, not have been good enough for us too? Instead, due entirely to the Scottish Government’s thirst for political difference and refusal to accept pleadings the sharp end, we now have indefinite postponement of any scheme while local councils do not have enough money to clean the streets.

And don’t forget that Circularity Scotland said it could make the scheme work without glass - in which case, it would not have gone bust and the Scottish National Investment Bank might have got its money back. To do otherwise, said Biffa would “completely undermine” the Scottish Government’s business credibility. All to no avail.

Chairman Watt assured the Holyrood committee: “We will do a complete drains-up piece of work on how we looked at the investment”. Well, that at least sounds a jolly good idea. Let us hope Ms Sturgeon is available to help with inquiries.

Brian Wilson is a former Labour Party politician. He was MP for Cunninghame North from 1987 until 2005 and served as a Minister of State from 1997 to 2003.