We all know what constitutes sharp practice - a broadcaster charging premium rates for callers to participate in a quiz show when the winner has already been chosen is a topical example - but the law often does not provide a simple way to bring such practice to a swift end. This will change when the UK implements the EU Directive on Unfair Business to Consumer Commercial Practices, which aims to harmonise EU consumer protection law. It will introduce a general prohibition on unfair trade practices, covering advertising, sales promotion, supply and after sales issues. Much consumer legislation (including the Trade Descriptions Act 1968) will be swept away.

The new law will prohibit outright 31 practices categorised as misleading or aggressive, such as tempting consumers with very low prices when no or few products are available at those prices; bogus prize draws; illusory closing down sales; paid for advertising masquerading as editorial content; or direct exhortations to children to buy products.

More widely, the law will also prohibit practices that are unfair, either generally or because they are misleading or aggressive. A practice will be unfair if it is contrary to the requirements of "professional diligence" and is likely to cause the "average consumer" to take a transactional decision (whether to purchase, on what terms and so on) which they would not have taken otherwise.

These are concepts relatively new to UK law. Professional diligence is assessed by reference to what might be expected to be honest market practice and good faith in that market. The average consumer is, according to the case law of the European Court of Justice, "reasonably well informed and reasonably observant and circumspect", perhaps akin to the man on the Clapham omnibus. But if the practice is directed at the vulnerable (such as children or the infirm) it will be assessed from their standpoint.

A misleading practice can include not only misleading actions but also omission of information which the average consumer needs to take an informed decision. If the consumer is invited to make a purchase (because he or she is given the crucial information in the advertisement, including price) omission of other specified information, such as the trader's geographical address or any taxes or additional charges, may be regarded as misleading.

The DTI are expected to publish draft Regulations in May 2007, providing for enforcement by means of criminal prosecution (fines and ultimately imprisonment) for the most serious infringements, with Trading Standards also having the power to seek civil injunctions. The UK will miss the December 12, 2007 deadline for implementation, but the new laws should be in force by April 2008. Self regulation by the Advertising Standards Authority will play an important role, since it is familiar with principles- based regulation and is likely to have a fair idea of the views of the average consumer. Will consumers themselves have new rights to sue? Probably not.

Although many of the provisions already exist in UK law or regulatory codes, the re-working of them in (often simpler) terms with sanctions that are easier to impose will force traders to re-examine current practices – for example those premium rate lines for quiz shows and customer services, enticingly cheap airline fare offers, and high pressure home sales pitches to the elderly for holiday clubs or heating. More will need to be disclosed up front in advertising.

The new law will be a good thing for the average and vulnerable consumer, and providing it is implemented in simple terms and enforced in a proportionate manner, also good news for business.

Rupert Earle is a member of Addleshaw Goddard's Advertising Group. He will be giving a keynote address on the Unfair Commercial Practices Directive at the forthcoming LexisNexis conference on Advertising Law in London on May 22nd. For further details on this conference visit www.conferencesandtraining.com/advertising

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