There was an exchange at Holyrood last week which, to me, summed up the often through-the-looking-glass nature of Scottish politics and, in particular, what passes for policy debate.

Responding to the First Minister’s statement on her programme for government, Scottish Conservative leader Ruth Davidson referred to the SNP’s policy of no tuition fees as having “seen poorer Scots less able to walk through the front gate of a university than those who live anywhere else in the United Kingdom”.

At this point John Swinney got very agitated. Although it doesn’t appear in the Official Report, from the press gallery I could hear the new Education Secretary shout “that’s not true!” over and over again in Ms Davidson’s direction.

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But as we learned a couple of days later when the Sutton Trust published its latest report – “Access to higher education for people from less advantaged backgrounds in Scotland” – it was true, indeed it’s an inconvenient truth that ought to shame any administration committed to tackling educational inequality.

I say through-the-looking-glass because when the Scottish Tory leader went on to attack the SNP’s “middle-class giveaways”, meaning “those who have most to gain from life-changing chances are those who are harmed most by this Government’s policies”, the government benches started heckling derisorily. Just to be clear, that was a Tory leader attacking middle-class subsidies.

Earlier, the First Minister had referenced her own back-story in order to justify her continuing faith in the benefits of “free” tuition despite considerable evidence to the contrary. Nicola Sturgeon said she knew from her “own personal experience that free tuition is essential to supporting working-class young people into university”. This isn’t a new line but remains a highly selective one, for it makes no mention of the (relatively) generous grant she would have enjoyed in the late 1980s, crucial student support eroded by many governments since, including the SNP.

The Herald:

At the same time there’s been a noticeable shift in the rhetoric. As with the United States constitution, Ms Sturgeon said that while “free tuition” was necessary, it was not in itself “sufficient”, and therefore other barriers, “financial, cultural and institutional”, that made young people from poorer backgrounds less likely to attend university than their more affluent peers also had to be broken down.

Thus the imminent appointment of a commissioner for fair access and the promised implementation of recommendations from the Widening Access Commission. But the trouble is that such is the sheer dogma surrounding “free” tuition fees that no one, including the First Minister, seems able to grasp that not budging an inch on that point might actually make many of those laudable aims harder to achieve.

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So the idea that free tuition fees marks Scottish higher education out as superior to that in England does not allow for any admission that the situation north of the border might actually be a poor way of improving access for young people from less affluent backgrounds, particularly when it leads to the system actually capping the number of places available to the very students it’s supposed to benefit.

When it comes to debt certain Nationalists are even more blinkered. Last week the new SNP MSP for Edinburgh Eastern, Ash Regan-Denham, made the extraordinary statement that in England “a young person will rack up huge debts to study at university; in Scotland, they will not”, apparently unaware that her own government’s policy of gearing student support towards loans rather than grants places precisely that burden on Scotland’s poorest students.

It is true, of course, that the average student in England will still end up with (considerably) more debt than those in Scotland, but when it comes to access this appears not to be a major disincentive. Thus the Sutton Trust’s central finding that Scots from the fifth most-advantaged areas are four times more likely to attend university than those in the fifth least-advantaged areas. The equivalent figure in England is 2.4 times.

The Herald:

Predictably, in responding to the Sutton Trust’s admirably lucid report the Scottish Government had to resort to (perhaps unintentional) misrepresentation, a spokesman erroneously claiming it hadn’t taken account of the fact that a significant proportion of higher education in Scotland took place in colleges. The report’s authors had, of course, covered that in a lot of detail, thus betraying a Scottish Government machine unfamiliar with its own figures.

To be fair, there has been some progress. The Scottish Government’s decision in 2012 to award 720 additional places at ancient universities specifically to those from the most disadvantaged areas has made a difference, proof that what Americans call “affirmative action” might not be politically popular but can pay dividends. But here’s the rub: using social class as a measure, there’s been no narrowing of the gap between Scottish students from managerial and professional family backgrounds and those from working class backgrounds since 1996.

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Tomorrow a seminar at Edinburgh University will focus on precisely that dimension, in other words how far “class” determines students’ access to higher education and how, consequently, class shapes the nature of Scotland’s universities. Indeed, one section of the Sutton Trust report reveals that while there’s been a downward trend in independently-educated pupils attending Russell Group universities, north of the border the reverse is true.

Now not all those will be from Scotland (where proportionately fewer pupils attend private schools), but the point is it means the “institutional ethos” of certain universities is getting posher. Research has shown that rising numbers of rUK, EU and international students attending ancient Scottish universities are likely to come more socially advantaged backgrounds, thus there’s an increasing danger, as the report says, that students from less-advantaged backgrounds may “feel that they do not fit in”.

Coming back to the main point, in this respect it seems clear that the dogma of “free” tuition hasn’t made much, if any, difference, in fact it might even have made matters worse, for if resources end up disproportionately directed towards the sort of students most likely to go on to higher education in the first place (i.e. those from more affluent families), then it’s hardly surprising that removing the (future) burden of fees will increase uptake from that particular group. The Scottish Government is good at pretending that somehow going to university incurs little cost beyond fees, but for children from less affluent backgrounds (and I was one myself) that simply doesn’t match the reality.

So to take the First Minister’s favourite case study (i.e. herself), someone from her background could now be relatively less likely to study law at Glasgow University than she was nearly 30 years ago.

Now how that squares with Ms Sturgeon’s broader commitment to “equality of opportunity for all” isn’t clear, or indeed her commitment to evidence-based policy making. The empirical evidence when it comes to higher education in general, and tuition fees in particularly, is overwhelming.