A retired Marine Department ship inspector, Wong Kam-ching, was sentenced to 15 months in jail on Thursday for making false statements to an inquiry into the 2012 Lamma island ferry disaster.
He was found guilty by the District Court earlier this month of a charge of perjury.
In sentencing Wong, Judge Timothy Casewell remarked on his "exemplary character" as noted by letters from his family, colleagues and acquaintances. He said Wong was now suffering from a recognised psychiatric illness and the loss of pension would be a severe financial penalty that would rob him of the security he had spent a lifetime to achieve.
The judge said while these were compelling circumstances, they were not exceptional enough to suspend Wong's sentence.
Wong had told a government-appointed inquiry that he had counted 12 children's life jackets on the Lamma IV ferry during a safety inspection five months before the deadly collision. This was in line with local regulations. But the testimony was disputed by crew members, who said the ferry never had any.
The inquiry, which ended in 2014, concluded that the absence of such life vests played a role in the loss of life. Eight children were among the 39 people who died in the disaster during the night of National Day in 2012.