Lavish TV commercials and glossy mailshots may be the staples of modern advertising - but for those without deep corporate pockets, shock tactics are more appealing.

Pressure groups, charities and even governments have employed graphic imagery and blunt slogans to highlight everything from animal cruelty to the dangers of drink-driving.

Canadian smokers are soon to be bombarded with pictures of diseased organs on the health warnings plastered across their cigarette packets.

In Britain, an advert for the children's charity Barnardo's, showing a baby preparing to inject itself with heroin, has been blocked by the Committee of Advertising Practice. It was due to appear in newspapers over the weekend.

However, when it comes to posters and magazine adverts, the public tend to stomach shocking and even gory imagery if it's for a good cause.

Steve Ballinger of the UK's Advertising Standards Authority (ASA) says people are less likely to complain about ads depending on who issues them.

"They're more forgiving of charities - but this does not give these organisations carte blanche," he said.

Mr Ballinger points to the 1998 campaign by the Commission for Racial Equality, which was itself branded "racist" and "offensive".

"Shocking adverts risk alienating the very people they want to reach. The debate over the merits of these ads also tends to obscure the issues they were intended to highlight."

Even the UK's beloved animal charity, the RSPCA, found itself topping a 1996 ASA poll of "offensive" ads - after it used a dead pony to illustrate the European trade in horse meat.

Second in the poll was a poster from the masters of "shockvertising" Benetton.

Despite the passage of almost 10 years, and the brevity of the actual campaign, the image of a bloody newborn baby plastered across billboards still sickens many.

"People don't find a picture of a newborn baby offensive - what they find offensive is having it blown up to a 36-sheet poster," says Mr Ballinger.

The 1991 poster attracted some 800 complaints.

"People objected to the crassness of using something shocking to sell a product - people don't like that being used to sell a jumper."

Pulling the wool?

The Italian clothing franchise has become used to weathering such accusations of crassness and is certain to be steeling itself for renewed attacks with its 2000 "communications campaign".

Having tackled such topics as war, Aids, racism and religion, Benetton's creative director Oliviero Toscani has now set his sights on capital punishment.

Toscani, a friend of pop artist Andy Warhol, has often used his free hand in corporate advertising - and control of Benetton's Colors magazine - to reflect on the brevity of human life.

For his latest project, using the pictures and stories of convicted murderers, he recycles the old gladiator salute - "We, On Death Row".

Asked what the debate surrounding the American predilection to execute its murderers has to do with the sales in Benetton's 8,000 stores worldwide, Toscani is likely to offer the same answer as when quizzed on the relevance of Mafia killings, the Kosovo conflict or racial strife.

"Nothing at all. Selling jumpers is the company's problem, not mine."

Dominic Mills, editorial director of Campaign Magazine, says Toscani's 16 years at Benetton reflect the company's almost unique self-image.

"It views itself as more than a company that makes clothes, with an obligation to do more than sell stuff - it has an obligation to raise awareness."

Although Benetton's global scattergun campaigns can appear a trifle laboured at times, they have certainly prompted thought among those who neither know, nor care, where their local branch is.

Mr Mills is more suspicions of the retailer's motives.

"They turn what is probably a small advertising budget into a big campaign which is written and talked about.

Talkin' loud, payin' (almost) nothing

"They are a mainstream operation, a slightly trendier version of Marks and Spencer, suggesting they are standing at the cutting edge."

Benetton is now one of the world's great brands - thanks also to its sponsoring of a Grand Prix team - but "shockvertising" has not entirely satisfied its commercial needs.

Franchise holders in Germany and France have gone to the courts, complaining the ads had sent sales into freefall.

Its "ethical" mission has also faltered. A poster showing three hearts - labelled white, black and yellow - was blamed in Italy for reinforcing fears over organ transplants.

Benetton's attempts to spark open debate - however sincere - have also had the effect of tightening advertising restrictions.

The ASA has now brokered a pre-vetting scheme, in which advertisers found to be "offensive" by the public submit future posters for scrutiny.

"Perhaps Benetton has wised up a bit and worked out that their message will be best received by a certain audience, and not everybody walking down the street," says Mr Ballinger.

"If they run in style magazines and the like, they will cause controversy rather than offence."

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