The police approach a man on Buchanan Street in Glasgow. He’s searched by the officers, handcuffed, then arrested and put in the back of the van. This happens a lot in Glasgow – it’s a busy city and there’s trouble every day – but the case of Angus Cameron is different. And it’s a case we should all be worried about.

Let me tell you who Mr Cameron is. He’s a Christian who regularly preaches on the streets in Glasgow; he has also preached at Cumnock Baptist Church, near where I live as it happens but the chances are he and I would not agree on much. He’s socially conservative. I’m socially liberal. He reads from the Bible to people in the street. I don’t read from the Bible to people in the street. As I say: chances are we would not be simpatico.

The point is: this is normal – people have different opinions and most of us, I hope, have friends and family with a range of opinions, beliefs and faiths. Like a lot of other Glaswegians, I’ve also seen Mr Cameron, and others, preaching in the street and I don’t agree with a lot of what’s said. Come to mention it, I also don’t agree with the anti-Israel activists I’ve encountered on the street recently. And I’ve seen trade unionists campaigning for strikes I don’t agree with, but that’s the nature of public spaces. I too would have the right to start shouting my opinions at people in the street but I don’t think it would end well so I’ll stick to this column instead.

Obviously, there’s always a chance with any public speaking or protest that it turns violent or disruptive and the police have to get involved. Fair enough. But that’s not what happened in Mr Cameron’s case. He was doing his thing peacefully, quoting from the Bible, with people walking by, and when the police approached him, he was polite and non-confrontational.

And yet he was arrested anyway. What the officer who first spoke to him said was there’d been a report of homophobic language. Mr Cameron was then told he was under arrest for breach of the peace with homophobic aggravation, put in the back of a police van and kept there for an hour. When he was finally released, he was told the matter would be dealt with “in due course”.

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It gets worse. A couple of days later, Mr Cameron received a call from the police telling him that he would not be prosecuted but that a “non-crime hate incident” had been logged against his name. Non-crime hate incidents, you’ll remember, happen when a person is accused of saying something that is not a crime but is supposedly motivated by hostility or prejudice around race, gender or other protected characteristics and the police have been keeping a record of them for ten years or so.

Fortunately, Mr Cameron was not prepared to accept what happened. With the support of the Christian Institute, he sued the police, won, and has now been given £5,500 for unlawful detention and £9,400 to cover his costs. Significantly, the record of the non-crime has also been deleted from Police Scotland’s records.

You may think there’s nothing much to worry about in all of this and that it’s worked out fine: Mr Cameron was cleared and compensated. You may also find it hard to take the side of the Christian Institute, which backed Section 28 and opposed gay marriage. And I guess most of us aren’t comfortable with parts of the Bible that may or may not be quoted in the street: Leviticus 20:13 for example, which calls for the execution of gay men. I believe some people would now call that “problematic”.

But if you do find it hard to be overly sympathetic to an evangelical Christian effectively getting a telling-off from the cops, think about the deeper consequences. The entire concept of non-crime incidents allows the police to stop someone speaking freely on the flimsy premise that someone else has been upset or offended. As the Court of Appeal said in 2021, in a case initiated by the campaign group Fair Cop, “the recording of non-crime hate incidents is plainly an interference with freedom of expression and knowledge that such matters are being recorded and stored in a police database is likely to have a serious chilling effect on public debate.”

Perhaps the fact that Police Scotland backed down in the case of Mr Cameron is a sign of hope; I hope it is. But sadly, the number of non-crime hate incidents recorded in Scotland has been increasing year on year; the force is also gearing up to launch a new specialist unit ahead of the Hate Crime and Public Order (Scotland) Act taking effect this year. The Act creates a new offence of “stirring up hatred” and the new police unit will be tasked with investigating examples of it. So if anything, things are about to get worse.

The fact that the Act has still not come into effect, despite being given Royal Assent in 2021, is itself significant. The official explanation is that the law was delayed to give the police time for “training, guidance and communications planning” but the problems run much deeper than that. During the consultation period, the Scottish Police Federation itself warned that the bill would be tantamount to the policing of what people think or feel. Now they’re stuck with trying to make it work.

The training and guidance is also probably aimed at trying to work out what is meant by “hate” because it is hopelessly vague and appears to rely on the perception of the person who hears the “hate”. No doubt, the man or woman who complained about Mr Cameron perceived the bits of the Bible he was quoting as hate, but the police should have told the complainant that Mr Cameron was doing nothing illegal. And the fact he won his case proves it.

The Scottish Government assures us their new law does not seek to stifle criticism or rigorous debate and that people will still be able to express controversial, challenging or even offensive views. But they also say people will only be able to do that if it is not done in a way that is “intended to stir up hatred or likely to stir up hatred” and that’s the problem. Like all bad laws, it’s vague, and vague means it’s open to confusion at best and outright abuse at worst.

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So let’s be kind to the officers who arrested Mr Cameron for a moment and assume they were just confused or misguided, although that’s a problem too. Think of the waste of time and resources. Think of the thousands paid to Mr Cameron. And think of the effect the new law may have on people expressing their legal opinions.

I suppose in the end we should be grateful Mr Cameron went to court. And the reasonable ones among us know upset or offence is no basis for a law (didn’t we learn that from the old days of censorship of the theatre by the Lord Chamberlain’s Office?). But I think we should also be worried that cases such as Mr Cameron’s are likely to happen again. And again. Let’s wait and see.