In September 2015, Zhang stirred controversy in Hong Kong after claiming that the Chief Executive of Hong Kong had a "special legal position which overrides administrative, legislative and judicial organs" and that separation of powers is "not suitable for Hong Kong".[4] Chief Executive Leung Chun-ying subsequently affirmed that his position is "transcendent" of the branches of the state.[4]
In November 2020, following the expulsion of four pro-democracy lawmakers from the Legislative Council, Zhang said "Hong Kong’s administrators must be patriots... and people who are anti-China and cause trouble in Hong Kong must be kicked out. This is a political rule under 'one country, two systems', and has become a legal requirement now."[6]
Also in November 2020, Zhang called for judicial reforms in Hong Kong.[7] In January 2021, Chief Justice Geoffrey Ma responded and said that the judiciary should not be reformed simply due to the pro-Beijing party being unhappy with the court's rulings.[7]
In March 2021, while on a trip to Hong Kong to survey opinions about planned changes to the electoral system to implement "patriots" ruling the government, Zhang claimed that he met with pan-democrats, without specifically naming any.[8]
On 2 March 2024, two days before the annual Two Sessions, it became public that Zhang would be leaving the Hong Kong and Macau Affairs Office; delegates attending the session called this a "normal leadership reshuffle".[9]
On 14 October 2020, the United States Department of State released a report on 10 individuals who materially contributed to the failure of China to meet its obligations under the Sino–British Joint Declaration and Hong Kong's Basic Law. Zhang was on the list.[13]