I was very pleased to see last week that the SNP members of the Salmond inquiry were asking much better questions than the week before. One of them asked Nicola Sturgeon if she could explain in what ways she had always done the right thing. Another asked where the First Minister got the lovely red suit she was wearing because it was so flattering against her skin. They were determined, it seems, to get to the truth.

Thankfully for everyone watching the proceedings, there were other members of the committee who asked more probing questions. The non-nationalists were also aware that their SNP colleagues seemed be trying to fill the hearing with minutiae about the welfare-at-work policy, so Jackie Baillie et al sat on their hands for this section, thereby maximising time for the juicier stuff about whether the First Minister broke the ministerial code.

The official answer to that question will be delivered by the Hamilton inquiry, but the bigger question in a way is where this leaves the First Minister. For a long time, she, and to some extent the SNP, appeared to be immune to the travails that normally bring down parties and leaders. There was plenty of mud to fling, but it just didn’t seem to leave a trace. Is that still the case?

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To find out, we can apply the political personality test that demonstrates why leaders lose momentum, or resign, or are brought down. The test has three parts, and a leader can often get away with failing one of them as long as they’re strong in one of the others. But if they start to do badly in most or all of them, that’s when things go wrong. Even for Nicola Sturgeon.

The first part of the test is performance: in other words, are you good at speaking? can you deliver a speech? or indeed can you answer questions at an inquiry and come across well? This area of the test can take you far even if you’re failing in other parts and it’s always been one of the First Minister’s strengths. She’s a good performer and demonstrated it again at the hearing.

If she has any weaknesses, it’s in the little things. Her tendency to roll her eyes for example, or sigh, or grumpily cross her arms. It’s not quite arrogance, but it’s not quite humility either is it? The other problem is that the performance of colleagues can also affect your score here. Who thought it was a good idea, for instance, for Humza Yousef to comment on the hearing by tweeting like a teenager high on Haribo? Confident performances can also drift into arrogance or aggression (Exhibit A: Ian Blackford). Having said that, performance is undoubtedly the First Minister’s greatest asset.

The second part of the test is competence and there are two sub-sections here: firstly, policies, philosophy, or “vision”, and secondly, the more managerial element in the ability to run things efficiently, and, until recently, Sturgeon was doing well on all of it. Her problem now, though, is that her response to the inquiry appears to expose less than competent management: proper notes weren’t kept, there are lots of things she says she forgot, and lots of public money was spent on poor decisions. In defending herself by saying she “forgot” or “didn’t know”, the First Minister has sacrificed some of her reputation for competence.

Which brings us to the third part of the test, which is trust. Again, Nicola Sturgeon has always scored well here, and there was no moment in the hearing where she was clearly nailed down for telling a lie. But there are signs of rot in the rafters: a Panelbase survey for The Sunday Times, taken after her testimony, showed the proportion of voters who thought she had been entirely honest was 35 per cent, and, in a way, this is the most dangerous area for her. Performance can be improved, competence can be regained, but a reputation for honesty, once lost or undermined, is hard to get back.

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What’s going to happen next depends on how all these parts of the test interact and a look at the fates of some recent PMs might be instructive. Gordon Brown, for example, proved competence can trump performance ability when he coped well with a series of early crises, such as the Glasgow Airport attack. But when the financial crisis hit and he took some of the blame, he lost his reputation for competence and didn’t have the performance skills to save himself.

It was similar for Theresa May – if you’re incompetent and a bad performer, it’s only a question of time – whereas for Tony Blair it was different. He was mostly seen as competent and able, and he was certainly a good performer, but a catastrophically bad score on trust, because of Iraq, eventually did for him and his reputation. In 1997, Mr Blair famously said most people thought he was a “pretty straight sort of guy” but by the end, there weren’t many people who believed that any more.

You can see the dangers in all of this for Sturgeon, can’t you? Her testimony was bad for her reputation on competence, and on trust, 40% think she was not entirely honest. But she has no disastrously bad score in any part of the test – yet – and, like Blair, she still scores highly on performance. In fact, she’s arguably even better than her former friend Alex Salmond, who’s not nearly as good at the empathy and emotion.

What might swing things for Sturgeon, in the end, is being able to regain some of the reputation for competence and the findings of the inquiries will be a critical factor, as will her handling of the easing of lockdown. However, the First Minister still faces a tricky reality here: she is not as immune as she used to be; she also does not pass the personality test nearly as well as she would have done six months ago, or even six weeks ago. What it means is that she’s in a very dangerous place. But the final results are still to come in.

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