People may not agree with him; they may not even like him. But outspoken commercial radio talk-show host Albert Cheng King-hon has become a high-profile barometer for public opinion in Hong Kong. While his confrontational style does sometimes offend, there is no doubting its appeal. His ferocious attacks on the government not only draw a big audience, they also make the self-styled 'Taipan' a prime target for any official attempt to stifle criticism. It is for this reason that Broadcasting Authority warnings, issued this month over two of Cheng's shows, are a cause for concern. The sanctions it imposed are, in a sense, routine. Every month, the authority, whose members are appointed by Chief Executive Tung Chee-hwa, issues reprimands to broadcasters, for everything from scenes of goat killing which might unsettle viewers to sexually suggestive advertisements for chocolate. But there are several factors which take Cheng's case out of the ordinary. Both warnings were issued as a result of his on-air grilling of government officials in April. In the first, he accused Ko Wing-man, then acting head of the Hospital Authority, of failing to properly manage public hospitals during the height of the Sars outbreak. Shortly after, Dr Ko made an emotional offer to quit. The following day, Cheng accused a Housing Department representative of being 'dog-like' for allegedly turning a blind eye to the extortion of workers. In its warnings to Commercial Radio, the authority found Cheng had breached its code of practice. His offence was to have repeatedly interrupted the two officials, failing to give them a sufficient right of reply. Essentially, he was reprimanded for being impolite. This is hardly an area in which we need official intervention. Interrupting is a necessary tool for any self-respecting chat-show host, used to ensure everyone sticks to the point. The world's top broadcasters would breach the authority's rule almost every time they hit the airwaves. There is also a lesson to be learned for the government concerning the way it seeks to get its message across. When spokesmen were needed for Cheng's show, two civil servants were left to stick their heads above the parapet. Dr Ko seemed particularly ill-equipped. His tearful offer won much public sympathy and, no doubt, led to many of the complaints received by the authority. If the relevant ministers had been put in the firing line instead, there might have been a different outcome. They would be expected to give as good as they get. The warnings issued to Cheng, who is also a South China Morning Post columnist, take on larger proportions when the authority's role in recommending whether broadcasting licences should be renewed is considered. Commercial Radio's licence is up for renewal next year. Secretary for Commerce, Industry and Technology Henry Tang Ying-yen has given an assurance that the warnings Cheng received will have no impact on the licence renewal decision. We accept that this is so. But the perception that the two are linked will be hard to dispel. The government ought to recognise that the Chengs of this world are good for Hong Kong. There are not enough of them. Robust debates of the kind encouraged by his show are an integral part of our vibrant society, helping officials keep in touch with the community and acting as an outlet for grievances. A mature government would tolerate such broadcasters even if they do indulge in what one local National People's Congress member has described as 'verbal violence'. They may not be polite, and they may occasionally offend, but the talk shows provide compelling evidence that freedom of expression is alive and well in Hong Kong.