The accused murderer of a teenage model failed in his attempt to escape trial on grounds of "acute psychosis."

A High Court jury yesterday ruled Lau Cheung-fai, 37, "fit" to stand a trial by a 5:1 majority following six hours of deliberation.

The case is now adjourned until February 20, when Lau will face a retrial before a fresh panel of jurors.

Lau, unemployed and married, had killed Kwok Wai-ming, 15, during a photoshoot session in his Mong Kok apartment before stuffing her into a suitcase and wheeled her to a nearby hotel, the court was earlier told.

The "necrophilic" man then had vaginal and anal sex with the girl's corpse before disposing of her remains in a refuse collection point.

The abrupt halt to the trial - started only two weeks ago - came as defense lawyer Michael Arthur argued last week that his client had been suffering from delusions.

Arthur added the delusions had "substantially affected" Lau's mind, rendering him unfit for trial - an opinion shared by two psychiatrists who testified for the defense.

During the course of the trial, the court had heard Lau claimed he had been thinking he was the "son of God."

Lau has also said he heard a voice telling him to dismember Kwok's body, but he was stopped by "angels" from within him.

However, prosecutor Martyn Richmond quoted another psychiatrist who suggested Lau was "capable" of facing trial.

In giving legal instructions, Justice Kevin Zervos yesterday said the six-member jury should combine expert opinions by all three psychiatrists.

Based on the evidence, they have to decide whether Lau suffered from "severe delusions," and whether he has the ability to tell the truth from illusions.

He would accept an outcome of either an unanimous or 5:1 majority verdict.

The panel then began discussions behind closed doors from 11:30am.

During the day, they had reviewed audio recordings of the three experts' testimonies and the judge's direction.

Lau originally pleaded not guilty to a count of murder in High Court. He had offered to plead guilty to manslaughter, but this was rejected by Richmond.

The indictment accused Lau of murdering Kwok on or about December 8, 2014, and dumping her body in Portland Street Refuse Collection a day after.

Lau had hired the teenager, nicknamed Siu B, for a private photoshoot for HK$500, but allegedly killed her after she refused to change into a costume he had prepared.

A forensic pathologist suggested the girl likely died of suffocation.