Last Friday, the former chief executive of Hong Kong, Donald Tsang Yam-kuen, was convicted by a criminal court on a charge of misconduct in public office. This is a first-of-its-kind conviction and again signals the willingness of Hong Kong's Department of Justice and the Independent Commission Against Corruption to investigate and prosecute even the most senior government officials. Mr Tsang was sentenced earlier today and received a custodial sentence of 20 months in prison.

The jury in Mr Tsang's trial reached its guilty verdict by a majority of eight to one after a six week trial and over 20 hours' deliberation. Mr Tsang was acquitted of a second misconduct of public office charge and the jury failed to reach a verdict on one charge of bribery under the Prevention of Bribery Ordinance (POBO).

All three charges were linked to various personal negotiations Mr Tsang had with a company chaired by businessman Bill Wong Cho-bau between 2010 and 2012 to rent and potentially purchase a penthouse apartment in Shenzhen. Around the time of these negotiations, companies owned or part-owned by Mr Wong had a number of applications (including a broadcasting licence) approved by the Executive Council of Hong Kong (Exco), which was chaired by Mr Tsang. The prosecution for misconduct of public office resulted from Mr Tsang's alleged failure to declare these personal negotiations to Exco.

The jury failed to reach a verdict on the bribery charge relating to the HK$3.35 million redecoration of the Shenzhen apartment, allegedly paid for by Mr Wong's company. Mr Tsang was accused of "accepting an advantage" (the redecoration work) under the POBO as a reward for granting applications sought by Mr Wong's companies.

The jury unanimously acquitted Mr Tsang of a second charge of misconduct of public office for allegedly putting forward interior designer Barrie Ho Chow-lai for a civic honour.

In his reported remarks, the sentencing judge indicated that he had originally considered a 30 month sentence, intended to reflect the seriousness of the offence given the office held by Mr Tsang. However, having received over 40 letters in support of Mr Tsang, the judge applied a discount of 10 months, giving him credit for a career of dedicated public service.

This week the Department of Justice was successful in its application for a retrial of the bribery charge, provisionally set for September. In the meantime, according to media reports, Mr Tsang intends to appeal his conviction.

Prior to Mr Tsang's conviction, the most senior public official to be convicted of misconduct or corruption charges in Hong Kong was Rafael Hui, the former chief secretary of Hong Kong. Hui's appeal, concerning conspiracy to commit misconduct in public office in relation to his dealings with property tycoon, Thomas Kwok, is due to be heard by the Court of Final Appeal in May.

Mr Tsang's conviction may prompt Legco to reconsider extending the application of the POBO to apply consistently to the conduct of the chief executive and other senior public servants. Legco last debated this in November 2015, but ultimately refused the motion.