Imagine if each episode of Porridge – Ronnie Barker’s sitcom about life in prison – had begun as follows:

“Norman Stanley Fletcher, you have pleaded guilty to the charges brought by this court, and it is now my duty to pass sentence. You are an habitual criminal, who accepts arrest as an occupational hazard, and presumably accepts imprisonment in the same casual manner. We therefore feel constrained to commit you to the maximum term allowed for these offences…

“Two weeks’ gardening, plus recommended attendance of a victim-offender mediation workshop.”

As well as somewhat undermining the sitcom’s premise, such a sentence might have struck viewers as being a shade on the lenient side. These days, though, it’s sounding less and less far-fetched. Because, in both Britain and the US, there’s a growing Left-wing campaign to get rid of prison sentences altogether. Not just for mere burglars like Fletch. But for every other type of criminal, too.

“Defunding the police” is no longer enough. Activists also want to abolish prisons – or, in their preferred term, “the prison industrial complex”. This year, a slew of books have been published on the subject. In the past month, we’ve had Becoming Abolitionists, by Derecka Purnell, and Abolition for the People, a collection of anti-prison essays edited by Colin Kaepernick. Other authors making the case include Shon Faye, in her book The Transgender Issue (which came out in September), and Amia Srinivasan, a professor at Oxford, in her book The Right to Sex (August).

For Sir Keir Starmer, it must be a worry. Last month, Dominic Cummings argued that the only way for Labour to win is to talk tough on crime. The trouble, he wrote, is that the party’s “activist base is extremely far out of whack with target voter opinion… You have communists wanting to empty the jails.”

This goal may seem a touch perplexing, but I think we have a duty to try and understand. So I’ve been reading the latest abolitionist books, in the eager hope that all would become clear.

Essentially, their argument goes like this. Prisons don’t work. Partly because so many ex-cons reoffend, but mostly because they fail to tackle the real cause of crime. Which, according to Left-wing abolitionists, is capitalism.

Capitalism, they explain, makes people poor and unhappy. And because they’re poor and unhappy, they commit crime. In other words, criminals aren’t really bad people. It’s just that capitalism makes them do bad things. So, when you think about it, criminals are victims, too. Which means it’s terribly unfair to punish them.

So what’s the solution? Simple. Socialism. Under socialism, you see, everyone will have everything they need: money, housing, work, happiness. So they won’t commit crime. Because they won’t need to. “In the abolitionist future I hope to build,” writes Derecka Purnell in Becoming Abolitionists, “[everyone] will receive their fair share of what they produce instead of a wage, which will prevent murders resulting from property, theft, robberies and burglaries.”

A sceptic might argue that, historically speaking, quite a few murders have been committed in socialist states – not least by the men leading them. And it isn’t easy to think of a larger “prison industrial complex” than the Gulag. Then again, perhaps the Soviet Union doesn’t count as “real” socialism. Failed socialist states never do.

Even so, our sceptic might wonder just how true it is that criminals commit crime because of capitalism. Did Harold Shipman lack a guaranteed basic income? Could the Yorkshire Ripper have been placated with greater local democratic control of community spending? Similarly, it may take time to persuade the electorate that Islamist terrorists will stop bombing us if we renationalise the railways, or that paedophiles will stop being attracted to children if we increase the supply of council housing.

Abolitionists do concede that one or two criminals may be beyond the help even of socialism. Instead of Prisons: A Handbook for Abolitionists, written in 1976 by Fay Honey Knopp, says it will be necessary to have “small community restraining and re-education centres”. Basically: nice little prisons, instead of nasty big ones.

Becoming Abolitionists, though, reassures us that they would seldom be needed. “In the rare case that a murder would happen, it would shock our communities, the entire world…”

Mocking these utopians may seem like shooting fish in a barrel. But it’s worth remembering: they aren’t random idiots shouting at pigeons in the park. They’re highly educated and critically-acclaimed intellectuals.

As history so often shows, though, the cleverest people can believe the silliest ideas.