Be honest with me. Are you Tory or non-Tory? Republican or Royalist? Unionist or nationalist? The type of person that saves your WhatApps or the type that deletes them every night just in case, say no more? Chances are if you’ve lived in Scotland for the last ten years or so, you’ve taken a side on all of those issues, and others, and talked about them quite a lot. Chances are: you’re sick to the back teeth of it.

So let’s look at something more interesting than the stuff we’ve been talking incessantly about: the stuff we’ve been ignoring. Class for example. We know that on the question of unionist or nationalist for instance, support for independence is highest in traditionally working class areas or areas of deprivation and generally reduces the more middle class you get. Exactly the same applies to Tory or non-Tory: the issue of class still has a powerful influence on your chances, or non-chances, of ever voting Conservative.

There are exceptions of course – I know plenty of working class Tories, and on the issue of independence, middle-class activists were some of the most passionate supporters of Yes (and the most irritating too, to be honest). However, having interviewed hundreds of people in the last few years about all kinds of issues – the SNP, Nicola Sturgeon, the Tories, independence, the pandemic, trans rights, taxation, you name it – it’s struck me again and again how often you can predict a person’s opinions based on their class and upbringing (me included).

You can also predict their lives as well. No doubt some of the more irritating middle-class Yessers tell themselves Scotland is more egalitarian than England, but one in four children in Scotland, and one in five working-age people, live in poverty, according to the Scottish Government’s own statistics. You’ll also be familiar with the Bearsden versus Maryhill stats which show life expectancy for people in the most deprived areas can be as much as 26 years lower than in the least deprived. And most of it, if not all of it, defined and driven by class.

Exactly how deep the problem goes was underlined this week by some new research from Glasgow University. What the researchers did was they looked at how volunteers reacted to different faces, what conclusions the volunteers drew about social class from those faces and how they rated the people for positive qualities such as competence, trustworthiness and so on. The results were depressing, if predictable.

Read more: Mark Smith: The great Glasgow bins rebellion: it could be the start of something

Essentially, the conclusion (although you may think it didn’t really need research to prove it) was that people are quick to form impressions of other people’s class and that it can have important, and negative, consequences. Wider, shorter and flatter faces were perceived as poor and lower status; the volunteers were also likely to judge people with that kind of face as more incompetent or untrustworthy. Conversely, narrower and longer faces were seen as higher status and more competent and trustworthy.

Of course, all of this applies before anyone has opened their mouths and spoken which is when Brits (Scots included) really start to judge people. But the conclusion is clear: we make a judgment on class quickly and it can influence how we treat others. In courts for example, you’re less likely to be convicted or sent to prison if you look middle class, wear a nice suit and say please and thankyou in a certain accent. It’s one of the reasons, among many others associated with class, why prisons are overwhelmingly populated by men and women from more deprived backgrounds.

So why aren’t we talking about it more? Perhaps it’s because class and status have always been so intertwined with Scottish life that we take its effects for granted. However, the relative silence on the issue, compared say to LGBTQIA+ rights or racism, is something we should be worrying about. I’ve been to several protests in the last couple of years that allege transphobia on university campuses and if there is transphobia it needs to be tackled. But I’ve yet to see a single protest about the lack of educational opportunities for working class kids. It’s also rare to hear campaigners on the issue of race mention class at all.

No doubt, research such as the project that’s just been done at Glasgow can be a small step forward; indeed, one of the researchers involved, professor of computational social cognition Rachael Jack, said she hoped her findings could help develop ways to prevent biased perceptions and I hope so too, even though the bias runs deep. I may meet you one day and I will judge you and you will judge me; it’s the way we are I’m afraid.

One possible way forward – although I’m phobic about knee-jerk laws – might be to legislate on the issue. As you know, race and sexuality are protected characteristics under equality law and it’s illegal to discriminate against someone based on those characteristics, but on social class: silence. There is no other issue that has a greater effect on education, work, and health, and yet the law says nothing.

The effect of this is that not only are people being unfairly treated in schools, universities, offices, and other places on the basis of class, it’s perfectly legal to do so. Basically, there’s a good chance employers, educators, lawyers, juries, you, me, will judge people on where they live, how they speak, and (as the Glasgow research shows) how they look and if the people being judged are denied an opportunity on the basis of those factors, there’s noting in UK law to prevent it.

That’s seem pretty extraordinary to me, especially given our hyper-sensitivity to other factors that can lead to prejudice. We should also be encouraging more research along the lines of the Glasgow project – at least that way we might be more likely to talk about the issue, and talking is a start. And a change in the law to make discrimination on the basis of social class illegal could mean employers would have to start properly measuring class-based inequality and that might be a step towards eliminating it.

Read more: Mark Smith: Intensive farming is wiping out Scotland's wild birds

I accept this raises hard questions for some of us. To what extent, for example, have the breaks I’ve had been down to merit, or the way I speak, the school I went to, or the impression people form about me based on the shape of my face? And to what extent are we really facing up to the effect social class exerts on all of us?

I’m not saying here that we shouldn’t be talking about the other stuff; of course not – keep talking about independence, the Tories, WhatsApps, and all the rest of it, because it matters. All I’m saying is we shouldn’t be ignoring the other big issue because, really, it matters more.