The Court of Appeal will consider whether powers under Hong Kong's Public Order Ordinance can be invoked to curb demonstrations. Three political activists are appealing against their convictions under the ordinance for offences arising from an allegedly unauthorised rally. Appeals arising from cases in magistrates' courts are usually heard by the Court of First Instance, but a judge yesterday ruled the higher court should hear the activists' appeal because it involved issues of great constitutional importance. The three - Leung Kwok-hung, of the April 5th Action Group, Christopher Fung Ka-keung and Chris Lo Wai-ming - were the first demonstrators to be convicted of criminal offences under the public order law. Leung, 47, known as Long Hair, was convicted in November in Kowloon City Court of holding an unauthorised assembly. Fung, 23, and Lo, 27, were convicted of assisting in organising an unauthorised assembly. The court found the three men had held an unauthorised rally at Chater Garden in Central in February 2002. The magistrates' court was told the defendants failed to obtain police permission a week in advance of the gathering.