'WHY is my home an illegal structure when I have been paying property tax and rates since I bought it for good money years ago?' That was the question repeatedly put to frustrated officials of the Buildings Department charged with the unpleasant task of evicting angry dwellers of illegal rooftop structures on two Tsuen Wan buildings this week. Their answer: rates were a tax payable on account of occupation and property tax was charged if a property was rented out; whether the structure was built legally or not was irrelevant. In fact, while it is the duty of the Buildings Department to pull down illegal structures, it is the Rating and Valuation Department's job to make sure you pay additional rates if you put up an extension to your property, even though that extension may be illegal. Sounds unreasonable? It certainly appeared odd, not only in the eyes of the Tsuen Wan rooftop dwellers who faced eviction, but also by former Legislative Councillor Chen Shou-lam. In 1978, Chen asked the Government if the payment of additional rates implied that an unauthorised extension to a property became authorised. 'Certainly not, Sir, the illegality of the structure is not relevant to their liability to rating,' said the then Financial Secretary Sir Philip Haddon-Cave. 'Rates are a tax payable on account of the benefits of occupation. And we do not seek to establish the legality of salaries or profits before imposing direct taxation on income,' he said. According to a RVD spokesman, the Rating Ordinance provides that any house, flat, office, factory or any other type of property which can be separately occupied is liable for assessment to rates and the occupier is required to pay whether the structure is legal or not. As for property tax, the Inland Revenue Ordinance provides that the owner of any land or buildings who derives rent from it has to pay the tax. An IRD spokesman said property tax was charged on all parts of a building separately rated under the Rating Ordinance. If the owner of an illegal structure derived rent from it, he was liable to pay tax on that rent, he said. Indeed, most long-time residents of Hong Kong are aware rooftop houses are mostly illegal. Even if they were not well versed with the technicalities of the law, coverage of confrontations between disgruntled residents and officials over the years have educated them. Even politicians have shied away from such rowdy clearances because they know there is not much political capital to be gained by helping a legally untenable cause. But pity the dwellers in the tens of thousands of illegal structures that litter the rooftops, back alleys and public spaces of the territory's older tenement buildings. Many are old, not well educated or recent immigrants from China who have ploughed their hard-earned savings to buy these shabby dwellings. They are the victims of deceit perpetrated by unscrupulous builders, real estate agents and previous owners who failed to tell the whole truth. How could they have figured out they had bought an illegal structure when the previous owner could show them piles of rates and property tax receipts bearing the official chops of government departments? In some cases, conveyancing was handled by a lawyer because the buyer was acquiring the legal ownership of a rooftop. To the buyer, the title deed for the rooftop which was in English - a language they did not know - was proof they were buying a legal dwelling. The formality led them into believing they were buying a dwelling which happened to be on the top floor, when in law they were merely buying the rooftop and the structure above was illegal. With authorities stepping up enforcement action against illegal structures, more confrontations can be expected. While residents of these illegal structures deserve our sympathy, officials deserve support in enforcing the law. The moment the authorities give in to demands of residents of illegal structures by treating them as owners of bona-fide property, we can be sure more illegal dwellings will be built to the detriment of public safety. But if officials want to spare themselves further abuse and alleviate the misery of those faced with losing their over-priced homes, they may want to explore a better course of action. Something must be done to dispel the wrong impression that if one is paying rates and property tax for a structure, then it must be legal. Asked what the Government would do to prevent such an impression from leading to more confrontations, a spokesman for the RVD said: 'It is never implied or stated by the department that the charging of rates or property tax gives any sanction or authorisation for illegal structures.' How about printing this short statement on every rates and property tax receipt? The RVD and IRD would be doing a great public service if they cared to take the trouble. Silence can easily be taken to mean acquiescence, especially if it is a government department that is keeping its mouth shut.