I’m taking the train down to London this week and my fellow passengers will know precisely where they are by the noises they hear, by which I mean a click, a hiss, and a glug-glug. They will hear these noises because my visit to England will be marked by the official opening of a can of M&S gin and tonic. Nice.

The reason I’ll only be drinking the G&T in England and not Scotland is because I’m a law-abiding sort of chap and the law says you mustn’t, absolutely mustn’t, drink alcohol on a ScotRail train but that it’s ok to do so if the train is English. So I will follow this rule and keep my G&T in my bag until I change at Carlisle and the border is behind me. Naturally, I’m a bit anxious that my G&T will be lukewarm by that point but I’m prepared to take that risk to ensure the law is upheld.

Of course, the reason we have the rule in Scotland, you will remember, is because ScotRail introduced it in November 2020 during the pandemic. With the kind of heavy solemnity that was common back then, and still is, ScotRail said they wanted everyone who travelled with them to do so in a safe environment and that people were less likely to keep masks on their noses and mouths or observe the official distance between humans when they’d had a few. In other words, the rule was supposedly to stop the spread of the virus.

There’s something else you may remember about that time as well which is that some people – including me while sipping a glass or two – warned that it is relatively easy to introduce such rules but it would be much harder to get rid of them, and so it has proved. In a tweet last week, ScotRail said “we’ve agreed with the Scottish Government that we’ll keep our current alcohol ban in place for the foreseeable future”.

Let’s read that again, it won’t take long: “We’ve agreed with the Scottish Government that we’ll keep our current alcohol ban in place for the foreseeable future.” That’s it. Nothing more. No reason. No justification. No explanation of why a rule that was explicitly, in their own words, introduced for one particular reason is still required even though the reason doesn’t apply anymore. It is announced, but not explained.

I realise some of you will welcome this move, perhaps because you’ve seen drunken behaviour on Scottish trains and I get that – I have too. I’m thinking of the guy on the Aberdeen-to-London overnight who by 3am was vomiting copiously and colourfully into his pint glass. Or the guy on the last train from Edinburgh who urinated, loudly and unapologetically, on the floor. Or the man – like me, a Scot far from home – who got on the Southampton to Glasgow, plonked himself into the neighbouring seat, opened the first of his six-pack, turned to me at the start of the 400-mile journey and said, ominously, “awright?” I think we’ve all had experiences of that kind.

But, unpleasant as all this is, bad behaviour was not, explicitly, the reason the alcohol ban was introduced on ScotRail trains: the rule was introduced because it was believed it would help to stop the spread of the virus. You may or may not accept that, but at least there was an explanation and that, it seems to me, is one of the first rules of good public policy: if you are going to do something, explain why you are doing it.

Sadly, in announcing the extension to the ban, ScotRail have now broken this important rule. David Simpson, ScotRail’s service delivery director, did say that the ban had been “successful particularly in containing some of the antisocial behaviour alcohol could often generate on some services”. But that was not the reason for the ban. Is it the reason for the extension?

If so, we deserve to know more of ScotRail’s thinking – and we deserve to see the evidence. For a start, it seems to me that the rule is widely ignored – just ask Mhairi “Tennents” Black. It also seems to me that the train staff do not have the will, or the capacity, to enforce it (and why should they? would you?). It’s also fair to ask whether there has actually been a drop in antisocial behaviour, how big it is, and why ScotRail think the alcohol ban has caused the drop. In other words, we are now breaking the second rule of good public policy which is that a policy should be based on evidence, not assertion.

There are other rules which are being broken here as well, one of which is that public policy should be effective. As anyone who’s been on the last train to or from anywhere on a Friday night could tell you, there is nothing to stop people getting tanked up and then getting on a train. And the reasons for anti-social behaviour and drinking go pretty deep in Scotland – ScotRail telling you that you can’t be anti-social or drunk on a train is going to do very little indeed, if anything, to change that.

There’s also the rule – and this is maybe the most important one – that any public policy should be proportionate. That vomiting guy on the overnight to London, or the urinator on the last train out of Edinburgh, is pretty unpleasant stuff but it is rare. Most people have a drink on the train without incident and yet their right to do so is being removed because of a rare event. I realise this sounds like the squeal of a middle-class person being denied their G&T but the point remains: it is not proportionate to remove a right that belongs to everyone because someone occasionally abuses it.

More broadly, ScotRail and the Scottish Government should also think about what the ban says about us. It says that Scots can’t be trusted to behave. It says that, given a whiff of alcohol, Scots will kick off or lash out. It suggests that trains are just places for Scottish people, lager glistening on their lips, to fight with each other. And while some of this is true, mostly it isn’t.

I’m not arguing that we should ignore Scotland’s problem with alcohol – of course we shouldn’t – but the idea of an “alcohol-free” zone on trains as a means of tackling problem drinking is as fatuous as the idea of a “smoke-free” zone as a means of tackling smoking – the latest figures on smoking, out last week, indicate that the number of Scots quitting or trying to quit cigarettes has dropped significantly. In other words, you can’t just declare that we are “free” of booze or fags, you have to deal with the reasons we indulge in them in the first place.

Does ScotRail get this? Does the Scottish Government? I doubt it. But at least, as I fume about it on the train to London on Wednesday, I can dig into my bag for a can of M&S G&T. I can open it and savour the click and the hiss. And then I can sip it gently as, out of the window, the country passes me by. England of course. England.

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