A former student who was denied the customary one-third sentence reduction for pleading guilty in a national security case has lost his ultimate appeal to cut his jail term.

Lui Sai-yu, who used to study at the Polytechnic University, took his case to the Court of Final Appeal after a lower court handed him a five-year sentence for inciting secession in April 2022.

He was accused of running a Telegram channel that contained messages deemed to incite hatred against the country and Hong Kong.

The District Court had decided that the starting point for Lui’s prison term should be five years and six months, then deducted six months off the sentence to reflect his guilty plea.

Usually, defendants who admit to their crimes receive a one-third reduction. In this case, Lui’s sentence would have been cut by 22 months, not six.

However, the six-month reduction was the maximum allowed under the national security law, which specifies that those convicted of a serious offence relating to inciting secession shall be jailed for between five and 10 years.

In handing down judgement on Tuesday, a panel of five judges at the top court ruled unanimously that sentencing provisions of the security law should be given priority in the event of inconsistency with local laws.

The judges also refuted the appellant’s argument that a five-year jail term should serve as the starting point for sentencing – which would allow for actual sentences to fall below that threshold.

"It cannot consistently be suggested that the legislative intention is for an offence found to be 'serious' for the purposes of that framework should then be dealt with by a sentence falling below the prescribed range," the judgement read.

The top court also ruled that a list of conditions to reduce a sentence set out in Article 33 of the law – including surrendering themselves and reporting on other offenders – is exhaustive.

It said the rationale of the provision is to provide offenders with an incentive to desist from endangering national security and to facilitate law enforcement, and a guilty plea is not a relevant mitigating factor.