THE circumstances under which dissident Lau Shan-ching was jailed in China will be considered when it is decided whether he can stand in the election, according to chief electoral officer, Carrie Willis. She dismissed suggestions that political relations between China and Britain would affect the decision on Mr Lau's eligibility. The electoral laws require all candidates to be ''ordinarily residing'' in Hong Kong for the 10 years preceding the nomination, but there is no definition as to how long a departure would lead to disqualification. Mrs Willis said it was difficult to set objective rules on how one was ''ordinarily residing'' in Hong Kong, noting that a number of other factors had to be considered by the returning officer receiving the applications. Mr Lau, a pro-democracy activist, was absent from the territory from 1981 to 1991 while serving a 10-year jail term in China for alleged involvement in ''counter-revolutionary'' activities. Yesterday, he submitted an application to the Kwai Tsing electoral office to register as a candidate. It will take about two weeks to ascertain his validity.