When in September the TV actor from The Thick of It, Chris Langham, was imprisoned for ten months after being convicted of downloading child pornography, I paused, murmured to myself: “Gosh — really? Just for looking at it?” Then, disgruntled at the silly defences Mr Langham mounted about “research” and having been abused himself, let the story go.

And when a few weeks back a young Muslim woman called

Samina Malik, the “lyrical terrorist”, was convicted, pending sentencing, of the crime of having written bloodthirsty poetry praising Islamic terrorism, I thought: “Crikey — really? Just for posting some stupid poems on the internet?” Then let that go, too.

But I can't get Samina Malik out of my head: she nags at my conscience. And news of this week's early release from prison of Chris Langham refreshes the unease I felt about the conviction.

It's about thought crime, isn't it? It's all about that dividing line, so fragile and disputable yet so precious to those who believe in liberty, between what we may say, write or think, and what may be so directly linked to action as to deserve the name of action. One is the proper preserve of the individual; the other the rightful business of the police. Where we draw that line is critical and can only be a matter of opinion. But we drew it wrongly in Ms Malik's case.

Samina Malik worked for WHSmith at Heathrow. She was 23, an age at which I was conspiring to cause bomb scares in Connecticut to disrupt a fundraising visit by the IRA.

We think and say stupid things when young. As a teenager I used to circulate prose and poetry too — and thank God none of it survives.

Variously obscene, seditious and (in my teenage brain) incendiary, my attitude-striking caused hardly a ripple. In retrospect I suppose it was part of a period of self-advertisement and self-definition through which many lively emerging adults pass. If there had been an internet in those days I would have posted it there. As it was, I succeeded only in getting banned from the school magazine.

Malik's work amounted to alyrical glorification of terrorist violence, including beheading infidels. It was no earthly use to any real terrorist but could be argued to have been potentially encouraging of a culture of admiration for Islamist terrorism. Frankly some of my Times columns could be misunderstood in this way, as could Cherie Blair's remarks about why Palestinians resort to terrorism.

But Cherie and I do not wear headscarves or work at tills. Malik was convicted (the first woman) under the new Terrorism Act, whose Section 58 stipulates that: “A person commits an offence if... he collects or makes a record of information of a kind likely to be useful to a person committing or preparing an act of terrorism.”

“You have been,” the judge told Malik, “in many respects, a complete enigma to me.” Oh come on, Your Honour. Don't you remember 1967, the student riots, the daubed walls, the imminent World Revolution? And before replying “Ah, but this is different; remember 9/11”, remember the Red Brigade, Remember Che, remember Cuba, remember that student revolution was taken very seriously in its day. What stopped the blind overreaction that might have given wings to insurrection was that the revolting undergraduates were white and mostly middle-class. Our parents never really thought of us as Other.

If Samina had been white I bet her counsel could have persuaded the jury that she was just a silly girl going through a phase. But Malik in her scarf came into court from the other side of a dark curtain where, in a world and a culture that we white British do not know, evil is believed to dwell. That was what convicted her. Her conviction thickens that curtain.

If I believed that the court made what was a factual mistake, wrongly estimating how much of a spur her poetry could prove to serious terrorists, and mistaking an indirect link for a very immediate one, then I could write off their verdict as wrongly informed. But there's something darker at work. The “link” we posit to real terrorist acts is an excuse. What we are really indicting Samina for is her state of mind.

We have found someone out thinking something awful, and we feel she has no right in this country to think or say it, and should somehow be stopped. Thought was the crime. The internet was just the evidence.

Which brings us to Chris Langham. He too (I believe) was convicted not for what he had done or was likely to do, but for what the court believed he had thought and felt. The technical terminology of the new world of IT gives a patina of deliberative action to behaviour that, before we had laptops, we used words like “look” and “see” to describe.

In what respect, in principle, does taking a book off a library shelf and opening it to look at a picture differ from “downloading” a screen image? Would someone be sent to prison for nearly a year for opening a book? I've lived and grown up with books, we all have, and can usually distinguish between browsing for reasons of morbid or titillating curiosity, and reading preparatory to action. We all know (whether or not we realise it) scores who have

looked at the most disgusting pictures for personal gratification, yet never dreamt of carrying those fantasies into action. We keep such behaviour in proportion.

I do not claim it never happens that indulging the imagination can be a “gateway” drug, leading to the real thing. I dare say poisoners and axe murderers have been disproportionately given to reading novels of crime and violence. But the rule of thumb of English jurisprudence has tended to be that we wait until they do it, or conspire to do it, before we arrest them. That is because arrest at an earlier stage may lead to injustices in the many cases of those who would never have gone on to the next stage.

The language of Microsoft seems to, but does not, usher in a different and less familiar world, in which the download is almost part of a chain of events. Yes, I've heard the argument that real children are abused to make the images people download; but we don't imprison people who knowingly buy goods produced by brutal child labour. And if computer graphics could (as they almost can) produce pornography without using real children and involving only virtual ones, do you think the prosecution would lay off? No, the argument about the instrumentality of the download is really just an excuse.

The real crime — for which internet exhibits were simply evidence — was what was thought to have been in Chris Langham's mind and desires. So long as he keeps his hands to himself I happen to think Mr Langham's mind and desires, like Ms Malik's poetry, are their own business.

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