The law is a dope: If they legalise marijuana, when they legalise marijuana, who would sell what to whom? Jerome Burne cases the joint.

You see it in a spat over a man's name: late last year, Bob Marley's estate announced that they were planning to sue the Philip Morris tobacco company for patenting the name Marley as a brand in France. Now what would Philip Morris be doing that for?

You feel it as a small stampede from the Right: Lord Rees-Mogg writes in favour of it; Woodrow Wyatt and Judge Pickles, Solomons come to judgment both, have pushed it in their columns. The Times and the Economist like the idea. And of course, old hippies, young ravers and sound-minded organs such as the Independent like it too: the legalisation of cannabis.

Most of these good people (the old hippies and young ravers apart) don't envisage the average pot-head being able to drift into the Dog and Duck and pick up a packet of Acapulco Gold Blend along with a pint and a bag of crisps. No government is going to take off all controls and let the market rip; dope is probably not one of John Major's basics, let alone Peter Lilley's. And yet there is a growing feeling that marijuana should be legalised, and that whatever form that takes, the free market and the big companies is the logical place for it to end up.

There are, of course, other models. For nearly 20 years the Dutch have operated a system of effective decriminalisation. Possession is still illegal, but in practice nobody is prosecuted for it and small amounts can be bought openly in coffee shops, although dealing is still outlawed. Supporters claim that it has made marijuana boring and that consumption is half the American level.

This is certainly the solution that Britain is edging towards - more than 45 per cent of possession cases are now let off with a caution, as opposed to 1 per cent a decade ago. But the system still needs an illegal dealer network to service it, with all the cost and criminality that involves - and it doesn't raise any tax.

The Dutch solution also favours home-growing for personal consumption. One or two plants indoors can produce enough to supply five joints a week, each containing about 5mg of THC (the active ingredient in cannabis), enough for one moderate user. Taking controls off home growth, according to a report by the Institute for the Study of Drug Dependency, might double consumption, but increased production was reckoned to be able to supply three-quarters of the total used, cutting the black market by 50 per cent and slashing prices.

But even this apparently simple measure introduces new problems. What, for example, is possession for private use, when at harvesting time plants could easily yield 400g, putting home users into the dealing category?

'The Dutch system is a pragmatic fudge,' explained Pat O'Hare, director of the Mersey Drug Training and Information Centre, 'but it's a favourite with politicians because it means that they can be seen to be doing something without being branded as soft on drugs. After all, there's nothing on the statute books.'

This is a fudge which is not acceptable to those in Britain who ruminate heavily on the matter, whether through a cloud of smoke or a cloud of jurisprudence: the present situation is, after all, a drag (man); put another way, it is a suppression of freedom and a bad, unenforceable law. The stoned ruminations of the committed and the deliberations of the wise argue for decriminalisation and regulation. Steve Abrams, who has been campaigning for legalisation these 30 years, has proposed a pounds 50 licence from a GP that would entitle users to an ounce a month from the chemist at half the black market price. The Institute for the Study of Drug Dependency report proposed setting up an equivalent to a poisons register. Dope smokers would have to give proof of identity, sign a receipt and pick up a small amount from a local drug store. An American professor has come up with a less medical variant, which gives everyone the right to obtain cannabis but also allows each state to set its own licensing laws, as is currently done with alcohol and gambling. But there is an old-fashioned ring to all this stuff. It involves wasting doctors' time, setting up state monopolies. In the end this will be, and probably should be, the world of Philip Morris and the other cigarette giants.

The belief that the cigarette companies are well into preparing for the day when packets of Red Leb or Marleys will be in all the shops goes back at least to the Sixties, but there is no very good reason to believe there is much in it. They have enough problems without dabbling in illegal drugs (anyway, highly valued, highly paid advisers such as Baroness Thatcher probably wouldn't go a bundle on it). But their time will come. Estimates of the current value of the UK marijuana market range between pounds 1bn and pounds 2bn. Geoffrey Howard-Spink, a leading figure in the British advertising industry, sees it this way. If marijuana were legalised, the business would at first be done by existing dealers. The big companies 'would come in when the market has settled down and when there was a clearer idea of health risks and profitability. That's when you start to get market segmentation and targeting special groups'.

The control that would exist would be for tax purposes. There could be bonded warehouses, licensed plantations and maybe licensed premises. The market would eventually be dominated by a few big producers because in a high tax business, where production costs only make up a small percentage of the final cost, there is little room for competitive pricing - just look at the cigarette market now.

Maybe Bob's executors are being a bit hyper about Philip Morris. But then again: 20 Marleys please.

SELLING IT: WHO AND HOW

'The obvious people to run a legalised marijuana market are the existing dealers. These people understand the market and are already serving it pretty well. License them, tax them, and dope-dealing becomes like any other retailing business. The price will fall dramatically. There will be intense competition to begin with and the ones who don't deliver the right quality at the right price will be forced out of business and the big companies will come in when the market's settled down.'

Geoffrey Howard-Spink, director of Lowe Howard-Spink, advertising agency.

'You would have to relaunch it completely. At the moment cannabis is far too heavily associated with hippies and rock'n'roll. If you are going to maximise market potential you are going to have to attract a lot of other groups. Besides, the youth market, which might be targeted with brand names such as Rajput Rebel and cigarettes that looked like loosely rolled joints, you'd also want to get to the executives, and that would mean changing the image of dope smokers as dozy, untogether pot-heads and instead stressing the relaxing element. 'A relaxed deal is a better deal', something like that. Other markets include health - emphasise therapeutic qualities like lowering blood pressure - and luxury.'

Julian Allason, Blackthorn Group, marketing man (opposed to the promotion of cannabis himself).

'For the middle classes the organic angle might be a selling point, and for superannuated arty types and West Indians who got into it in the Fifties another approach would be needed. I see the connoisseur idea working. You'd get different growths of grass in the way you have cigars or single malt whiskies, maybe even mailing shots inviting connoisseurs to join a club. 'Just pounds 100 a year to sample the world's finest grass'.'

Peter York, marketing expert and trendspotter. ('Can't stand the smell of the stuff. I'm the original Disgusted of Tunbridge Wells.')

(Photographs omitted)