The extracts we’ve had so far from Nicola Sturgeon’s memoirs seem to be focusing on all the negative stuff – the police investigation into her, the police investigation into her husband, the police investigation into her mentor Alex Salmond (the police do feature a lot in the book). So maybe today, we could talk about something more positive, something that’s widely seen as one of the lasting legacies of Ms Sturgeon’s time in office (there’s a catch by the way).

The subject I’m referring to is transport, specifically green transport, specifically green buses. There was a time, while at the height of her powers, when Ms Sturgeon loved posing behind the wheel of an electric bus or standing over it with a charging cable in her hand. She was also very proud of the free bus travel policy for everyone under 22 years old. All those thousands of passengers not paying for bus tickets would, she said, improve young people’s access to education, work and leisure and support the Scottish Government’s ambitions on sustainable travel and the climate.

But the real killer with all public policy is the unintended consequence, the one thing that the advisors and the spads didn’t think of sitting around a table making the policy up and composing press releases and tweets. In the case of free travel for under-22s, it was the increase in anti-social behaviour it caused, because some young people realised pretty quickly that they could hang around on buses or head into town without it costing them anything and in many cases it hasn’t ended well. As I say: unintended consequences.

A bit harder to spot are the........

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