LAU Shan-ching is eligible to run for the House of Commons, but he can't stand for Hong Kong's district boards. This startling fact shows just how out of date and farcical Hong Kong's electoral rules are. An international survey shows Hong Kong's 10-year residency requirement for candidates running for the district boards, municipal councils and the legislature to be an exception rather than the norm. According to the Inter-Parliamentary Union - which Hong Kong is not a member of - the only other countries which have a similar rule are Costa Rica, Norway and Zimbabwe. In the case of Zimbabwe, the requirement applies to candidates running for the Senate, while House of Assembly candidates need only be resident for five years. A survey conducted by the union in 1985, for which 83 legislatures responded, found that as many as 35 countries impose no residency requirement on their candidates, although the almost-universal requirement for citizenship ensures they must be born or have lived in the country. Another 30 countries merely require their candidates to be in the country or have been resident in the country or their constituencies for one year or less. China, Hong Kong's sovereign after 1997, imposes no residency requirement on prospective voters or candidates for the people's congresses, both at the local and national levels. The United States requires those who run for the Senate to have been a citizen for nine years and those for the House of Representatives seven years. There is no requirement for prior residence in the state, but a candidate must be resident in the state he or she represents when elected. In Canada, the candidates for national parliament need only reside in the province in which they stand and there are no requirements on the duration of residence. At the provincial level, residency requirement ranges from no more than a few months to one year. In Australia, three years' residence in the country is required for candidates running for either of the houses of parliament. There is a strong argument for Hong Kong to follow the worldwide preference for having a requirement for only a short duration of residency, particularly for those who are already permanent residents by birth. As for those who have acquired permanent resident status by having resided in Hong Kong for seven years, there is no point in requiring them to be here for another three years before they can stand for elections. In a place such as Hong Kong, where a significantly large proportion of its population is highly mobile, it is unreasonable to require those who already have permanent residency status to have to be ''ordinarily resident'' in the territory for 10 years before nomination. A number of incumbent Legislative Councillors and members of the two municipal councils and the district boards have admitted to having spent time studying or working overseas before running for office. Instead of asking returning officers to make a ruling on whether a candidate has been ordinarily resident in the territory for 10 years, Hong Kong could do better by shortening the residency requirement to no more than one to three years. After all, it doesn't take 10 years for anyone who is keenly interested in serving the people to understand a place. Mr Lau, in asserting the requirement of 10 years' ordinary residence in Hong Kong should not apply to him because he was unjustifiably jailed in China, also raised the issue of the integrity of China's legal and judicial systems. While many people in Hong Kong and the West have serious reservations about China's judicial machinery, the implications of Hong Kong second-guessing the ruling of a Chinese court, or any other foreign court, needs to be carefully considered. The issue is important because Section 19 of the Electoral Provisions Ordinance provides that a person cannot be nominated as a candidate if he or she has been convicted of any offence in Hong Kong or any other territory and sentenced to imprisonment, whether suspended or not, for a term exceeding three months without the option of a fine during the 10 years before the date of the election. The law does not seem to acknowledge the fact that courts in different jurisdictions don't always readily accept the rulings of one another. In Mr Lau's case, the Boundary and Election Commission did not need to invoke this section to disqualify him because he was convicted in 1981. But there is nothing to stop another person who has been jailed overseas, for what he claims to be unjustified reasons, from making a similar challenge. Which leads us to the more important question of why an ex-criminal should be disqualified from standing for public office. There is an argument for barring such people for a certain period to ensure the quality of the candidates, as opposed to the counter argument that ex-criminals should not be discriminated against because they have already served their sentences. In Hong Kong, public sentiments are more likely to favour the former view than the latter. But should we follow Britain, where ex-criminals are not barred from running for office if they were convicted overseas? At first glance, such a rule may sound absurd because it means you can still be considered a gentleman in your home country even though you are a crook abroad. However, as the law of a country is a reflection of its unique cultural and political values, should we so readily accept the judgment of a foreign court in assessing the integrity of a person trying to run for public office in his home country? This is not to say one should not obey a host country's laws while overseas. But why should a Hong Kong person be barred from running for the district board if he had been sentenced in an Islamic country for drinking? Mr Lau argued that he was convicted of a crime in China which has no equivalent in Hong Kong law. He has a point, although it is inconceivable for Hong Kong to ignore the ruling of a Chinese court after 1997. There is nothing the authorities can do now to change the rules for next month's district board elections, but far more important elections for the Urban Council, Regional Council and Legislative Council are due to take place next year. A review of the eligibility criteria of candidates must now begin so that no one will be unfairly barred from running next year. Such a review would no doubt be watched closely by China, whose Preliminary Working Committee is working out the criteria determining which board members and councillors can hop on to the ''through-train'' in 1997. The bottom line must be to allow the people to have the final say on who can be allowed to serve them.