 He gave up his Canadian citizenship in 2004 to comply with local election requirements for direct elections to the Legislative Council of Hong Kong.He won a seat in the Legislative Council and tackled vital issues such as the opening up of the public airwaves, imposing tighter tobacco control, introducing food labelling, and regulating against unscrupulous practices in the sales of residential flats.Cheng was opposed to the privatisation of the government's shopping malls and car parks in its public housing estates.