Central Policy Unit
Lam Wing-kee, one of the five Causeway Bay booksellers who went missing from October 2015 returned to Hong Kong and revealed at a press conference in June 2016 that he was kidnapped at the China–Hong Kong border in October and put through eight months of mental torture. The controversy ignited fears that mainland law enforcement officers might have acted within the territory of Hong Kong and shook Hong Kong's confidence in the one country, two systems. Professor Lau Siu-kai, former head of the Hong Kong government's think tank, the Central Policy Unit, worried that more people might vote for pan-democracy camp in September's election.