Most mornings when I walk out of Tara Street Dart station, I am confronted by a large group of people openly buying and selling drugs. Like all successful entrepreneurs, they have carefully selected this business location. They have chosen to trade here because of its infrastructural links, its young customer base, its highly competitive environment and its unique vantage point (you can see people coming from every direction).

The first time the drug pushers appeared, we rail passengers stared at them in horror and astonishment. But as time passed they have become as much a feature of the egress from Tara Street station as the Herald AM and Metro distributors. Even the tourists appear to subconsciously pick up the vibe that this is a normal Dublin streetscape.

So commonplace has this scene now become that one of these mornings I expect to open my bleary eyes 50 yards down the street to discover that instead of my usual free newspaper I have accidentally picked up six wraps of heroin. At least I will have no difficulty off-loading them, since there is a large group of drug dealers operating along the Liffey Boardwalk and another on Wood Quay who use the plant display outside the Civic Offices as a botanical hiding place for their stock.

In fact my entire route from Tara Street to the Four Courts is one continuous, open drugs mart. The only way in which it differs from a supermarket is the absence of security guards, since the gardai seem to have given up.

It has been profoundly dispiriting to see this open drug dealing increase in the past few weeks and the speed with which the public has become accustomed to it. The drug addicts pass among commuters and tourists in a parallel universe, like the ghosts in The Sixth Sense that could only be seen by the boy. He would surprise adults by saying “I see dead people”; a phrase that is startlingly applicable to many of the addicts.

What can have made this army of drug-addled zombies so unafraid of public outcry that they deal openly outside one of our busiest railway stations and on the steps of Dublin’s main civic-administration building? Perhaps they have obtained encouragement as to the way society now thinks about drugs from a new book by Paul O’Mahony, a Trinity College Dublin criminologist, entitled The Irish War on Drugs: The Seductive Folly of Prohibition. Its thesis is that prohibition is emotionally driven and fundamentally irrational, and flies in the face of overwhelming evidence that it does more harm than good.

I was worried that the book might change public opinion until I saw the title of chapter 10: “The promise of alternative approaches: the possibility of a Kuhnian paradigm shift in the way we think about drugs”. Not a slogan to motivate the masses towards legalisation of drugs.

Unfortunately O’Mahony is not alone in believing that the best solution to certain crimes is to give up trying to prosecute them. The local authority in Durban has called for legalised adult entertainment venues for the 2010 World Cup. It said that while prostitution was illegal in South Africa, it could not ignore the fact that the sex industry thrives during events such as the World Cup. It is difficult to imagine more flawed reasoning.

Last week, the English Court of Appeal quashed the convictions of three men who worked for a hydroponics company in Derby for conspiracy to aid and abet the production of cannabis. The prosecution said they had supplied equipment to cannabis growers reasonably foreseeing that it would be used illegally. There was no proof anyone had used the equipment to grow cannabis. Lord Phillips ruled that there can be no conviction for aiding and abetting unless the offence is shown to have occurred.

Of course there are many legitimate reasons for buying and selling hydroponics equipment. Presumably the reason why so many young unemployed men living in cities buy it, however, is so that they can grow strawberries in their basements.

In the face of this liberal onslaught against criminal law, it is worth reminding ourselves that there is nothing wrong with society deeming certain activities to be inherent vices and to punish them as such. Most drug addicts have decided to refuse to engage in society, and to sponge off the rest of us instead. What O’Mahony bemoans as “condemnatory, repressive and punitive attitudes” are the only attitudes that these addicts are capable of understanding and are labels we should all be proud to wear.

It is daft to argue that criminalising drugs makes them more attractive to people who are antipathetic to authority. That’s like saying that me declaring my television belongs to nobody else but me makes it more attractive for someone who does not believe in private property to break into my house and steal it.

One of the features of the Celtic tiger was that the division between the drug-abusing underclass and the rest of society was enforced and the underclass became invisible. Now the recession has hit, the underclass is visible again and it is only a matter of time before we can all see the ghosts and, more worryingly, they can see us. Against such a backdrop, abolishing any of our criminal laws seems like a particularly inopportune idea.

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