He then served as the second Secretary for Justice of Hong Kong between 20 October 2005 and 30 June 2012, under Donald Tsang Yam-kuen.

[3] On the Hong Kong Legislative Council oath-taking controversy, Wong described the National People's Congress Standing Committee interpretation of the Basic Law as a "pity" and "avoidable".

[4] When former Chief Executive Donald Tsang was found guilty of one count of misconduct in public office in 2017, Wong personally wrote a ten-page letter of mitigation, stating that "[Tsang's] significant contributions to Hong Kong in the past over 4 decades should be properly recognized.

He received several hundred thousand Hong Kong dollars as a wedding gift from his wife's wealthy family, which he, in turn, gave to organisations for the homeless.

He has also served as Vice-Chairman of the CEDAR Fund and Member of the Steering Committee and Volunteer of the Hong Kong Christian Concern for the Homeless.