THREE mainland legal experts from the Preliminary Working Committee (PWC) arrived in Hong Kong last night on an unprecedented trip to reply to criticism over its proposal to water down the Bill of Rights. The trio are Shao Tianren, co-convenor of the PWC's legal sub-group; Xiao Weiyun, political sub-group co-convenor; and Wu Jianfan. Attending today's session, at the headquarters of Xinhua (the New China News Agency) are local deputies of the National People's Congress (NPC), Chinese People's Political Consultative Conference and Hong Kong affairs advisers. Some of them have opposed the PWC proposal, most notably local deputy to the NPC Liu Yiu-chu. The sub-group finalised its proposals on the bill this month. It proposed that key provisions relating to the overriding power of the bill be removed and a number of laws changed because of the Bill of Rights being reinstated after 1997. Local sub-group member Tam Yiu-chung said he had no idea whether the trip signalled a change of mind in Beijing in view of fierce criticism on its proposals. 'But it is still a good thing that they can listen to the opinions of Hong Kong people and try to explain the rationale,' he said. 'Given the limited information, the public fails to understand the PWC proposals. They do not understand why some original laws should be reinstated and in what ways the Bill of Rights contravene the Basic Law.' He did not rule out the possibility that the issue would be tabled for discussion at the sub-group's meeting in Beijing next week. In a statement released last night, the Law Society urged the sub-group to give sufficient reasons for its proposals. It said the bill was consistent with Article 39 of the Basic Law, according to which the International Covenant on Civil and Political Rights as applied to Hong Kong should be implemented through the laws of the Special Administrative Region. The bill was an implementation of the covenant, the society said. Any laws inconsistent with the covenant were liable to be repealed by the bill and the NPC under the Basic Law. As the Basic Law could only be amended by the NPC, it dismissed China's fears over the bill because the post-1997 constitution would have its supremacy over the bill.