Yiu graduated from the
University of Hong Kong (HKU) with a degree in surveying in 1998 and later earned master's and doctoral degrees from the HKU in 2000 and 2002 respectively. He is a member of the
Hong Kong Institute of Surveyors, the
Royal Institution of Chartered Surveyors and various professional organisations. He also started teaching as an instructor and lecturer at the
City University of Hong Kong in 2002, became an assistant professor at the
Hong Kong Polytechnic University, the City University and the University of Hong Kong and an associate professor at the
Chinese University of Hong Kong. However, the
oath-taking controversy sparked by two localist legislators
Sixtus Leung and
Yau Wai-ching of
Youngspiration led to the unprecedented legal challenge from
Chief Executive Leung Chun-ying and
Secretary for Justice Rimsky Yuen against Yiu. On 7 November 2016, the
National People's Congress Standing Committee (NPCSC) interpreted of the Article 104 of the
Basic Law of Hong Kong, standardising the manners of the oath-taking when taking public office. As a result, the duo were disqualified by the court. Subsequently, the government launched a second legal action against Yiu and three other pro-democracy legislators,
Lau Siu-lai,
Nathan Law and
Leung Kwok-hung, which resulted in their disqualifications from the Legislative Council on 14 July 2017. He ran again in the
March 2018 Kowloon West by-election for the seat left vacant by Yau Wai-ching after defeating
Frederick Fung and
Ramon Yuen in a three-way primary coordinated by the
Power for Democracy. Despite rumours that his candidacy could be foiled on the basis of National People's Congress Standing Committee interpretation of the Basic Law being applied to the entire term of the current legislature, Yiu survived the disqualification. However, he lost to
Vincent Cheng from
Democratic Alliance for the Betterment and Progress of Hong Kong (DAB) with a narrow margin of 2,419 votes, becoming the first pro-democrat to lose in a geographical constituency by-election since 1992. ==Notes==