YOU probably got your letter from Nicola Sturgeon this week and the message was clear. We will get over this, she said, this is not forever, and we will come through it stronger – grave and important phrases which I’m sure, like me, you will recognise from the impressive oeuvre of Donna Summer. But, on the whole, the tone of the letter was about right: sober, sensible, scientific.

So why did the First Minister have to go and spoil it by talking about face coverings? Speaking at one of her briefings, she told us that, although the evidence was limited, it was now the Scottish Government’s position that face coverings should be worn in public places like shops and buses. She made it clear she was talking about coverings such as scarves and not medical-grade masks. She also made it clear a face covering was not a substitute for social distancing.

But what a confused and muddled message that is. What was she thinking? Are we now to wear scarves all summer long, like Tom Baker arriving on an alien planet (in which case I approve) and if so, where is the evidence that a scarf over your face has any effect? Ms Sturgeon also said her message did not include medical-grade face masks, so does it include non-medical-grade masks? Like I said. Confusing. Muddled.

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The fact that the message on face coverings was so muddled was also a rare mis-step for the First Minister. Like the other UK leaders, she’s based her briefings on evidence, but she’s also tried to make them easy to understand, and she’s been sensitive to how her words could be interpreted, as well as the possible effects on our way of life. But this time, I’m afraid, she’s failed on all of those counts.

First, the details of what Ms Sturgeon announced. She was referring, she said, to face coverings made of cloth, such as a scarf, which presumably includes the kind of cloth masks you can buy online. But where’s the evidence on the usefulness of scarves? Does the material make a difference? Does how you wear it have an effect? It would be difficult to wear a scarf on your face without gaps, and you’re also going to be touching it to adjust it. It’s hard to see the point.

As for masks, talk to doctors. They don’t all agree of course, but the ones I’ve spoken to are deeply sceptical. As a way of protecting the wearer from infection in public, masks are next to useless. As for preventing others being infected, there may be some efficacy, but again it’s likely to be compromised by how the mask fits, how it degrades over time, and by the fact that people will touch the mask.

Then there’s the behavioural science. Ms Sturgeon said in her briefing that face covers were not a substitute for social distancing, but when people wear a mask, their behaviour is likely to change. They will think they’re safer and go out more and for longer, not wash their hands as much, and get closer to people – in other words, far from decreasing the risk, face masks could end up increasing it.

We also shouldn’t underestimate the effects on our culture. There are some countries in which masks are common, but in Britain we tend to feel quite a bit of cultural and historical angst about people covering their faces in public and that openness needs protecting. People may say the risks to health matter more, but the response to coronavirus isn’t just about the risk to health, it’s about balancing the risk with other risks, to the economy for example, or our way of life.

Some of the First Minister’s defenders have said in response to all of this that her message was misinterpreted. She wasn’t talking about face masks, they say, she was talking about face coverings. But what exactly would they suggest we use to cover our faces if not a mask? One of the flags left over from the cancelled independence marches perhaps? Or maybe a copy of Scotland’s Future, the white paper on independence, held discreetly over the nose and mouth?

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The point is that when a politician speaks, they do it in the real world and their message is received in the real world, and as a result of the First Minster’s pronouncement, more people are going to start wearing masks. At best, it will be a waste of time; at worst, it could increase the spread of the virus. But it could also change the principles of openness we take for granted. I do not want to see that. I will be defying the government advice. I will not be wearing a mask in public.

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