The death sentence has left many questions unanswered, legal experts said. Not only was it uncertain whether Li had received a fair trial, but there was the danger that the mainland could continue prosecuting Hong Kong crimes, they said. 'The most significant point revealed by this case is that we don't know what 'one country, two systems' means,' said Fu Hualing, a University of Hong Kong academic specialising in mainland law. He said it was unclear if Hong Kong was considered part of China under mainland criminal law. 'China has never sent any of its nationals to any other country to face criminal trial. In this sense, it was just following tradition with the Li Yuhui case,' Mr Fu said. 'But if Hong Kong is considered a part of the PRC, then it is supposed to send Li back here.' Mainland authorities claimed they had the right to prosecute Li because, under Chinese law, they can prosecute its nationals even for crimes committed outside the country. But critics said Li should have been tried in Hong Kong, where the crimes were committed. SAR authorities, who never requested Li's transfer, said if they had they could be put in the awkward position of having to reciprocate if mainland authorities demanded the transfer of a Hong Kong resident. Li's case also raised concerns that Hong Kong residents could be subjected to prosecution on the mainland for crimes allegedly committed in Hong Kong. 'If a Hong Kong person does anything in Hong Kong that's not considered illegal here but is illegal in China, when he goes back to the mainland he may be arrested and tried without any chance of being extradited to Hong Kong,' said Raymond Tsui Wai-nam of Human Rights Monitor.