A one-time top aide to former Hong Kong leader Leung Chun-ying has lost an appeal against a conviction for conspiring with his financial officer to defraud the city’s market regulator almost a decade ago.

Barry Cheung Chun-yuen, who just passed his 64th birthday behind bars on Tuesday, is serving a four-year jail term at the maximum-security Stanley Prison for fraud and conspiracy to defraud over his attempts to keep his commodities market afloat before authorities shut it down in May 2013.

Collecting the Court of Appeal’s judgment on Wednesday, the disgraced businessman appeared to have lost weight compared with when he stood trial in the District Court in 2020. He had a brief conversation with his lawyer before prison officers escorted him away.

Cheung, who founded the now-defunct Hong Kong Mercantile Exchange (HKMEx), acted as Leung’s campaign chairman when the latter ran for the city’s top job and later as an executive councillor after Leung took office in 2012.

But he stayed less than a year in Leung’s de facto cabinet before resigning from all public posts following two decades of public service when the Securities and Futures Commission (SFC) launched an investigation into HKMEx.

He was convicted in July 2020 for conspiring with his then chief financial officer Jacky Choi Tat-ying to hide the true financial position of the platform and for misleading the SFC into letting HKMEx keep its authorisation to provide automated trading services.

He was also found to have made false representations that led to a financial institution lending him HK$30 million (US$4 million) in April 2013 for his firm based in the British Virgin Islands.

In seeking the court’s permission to lodge an appeal, Cheung’s counsel argued the appellant had no intention to deceive the SFC, as he had genuinely believed the watchdog would be flexible with the enforcement of operation requirements, and would not be deluded by bogus financial records.

The counsel also said participation in “sharp practice” was not dishonest and did not amount to a conspiracy to deceive.

Justice Andrew Macrae, a vice-president of the Court of Appeal, rejected the submissions by citing Choi’s testimony in finding that it was Cheung’s clear instruction to “make the balance as great as possible”.

The judge also agreed with the lower court’s ruling that Cheung bore the requisite intent to commit the crime given the high stake he had in the platform and the loss he would suffer if it was shut down.

Cheung can still renew his application for appeal but will risk spending longer in prison if his bid ultimately fails. His release is expected in March 2023.