In delivering its 12 August 2026 ruling on The King versus Ko, the majority of the High Court dismissed the Crown appeal against the August 2025 decision of the New South Wales Court of Criminal Appeal to quash the drug importation conviction against Tsz Cheung Herman Ko, as the trial judge failed to direct the jury to the second mental fault element required to establish the offence.
Ko was found guilty of attempting to import a commercial quantity of two border-controlled drugs on 16 July 2024, which alleged the importation of a commercial dough mixer from Canada to a warehouse in Wentworthville in western Sydney on 19 October 2021. Ko did this on behalf of his friend, taxi driver Yuan Long Yang, and the mixer’s final destination was to be a bakery in Burwood.
The consignment had been seized in Toronto, however, as part of a joint inquiry between Canadian authorities and the Australian federal police. They found bags containing a kilogram of two illicit substances: methamphetamine, also known as the drug “ice”” and phenylethylamine, which is a drug analogue with similar effects. The illicit drugs were then substituted with an inert substance.
At trial, Ko maintained that he acted on the direct instructions of Yang, he was unaware what was being brought into the country and that he was not paid for his services. Yang was then arrested by the AFP, during a controlled operation in October 2021, while Ko was not arrested until March 2022, when his Beecroft house was raided and evidence of his involvement was found.
On appeal, however, a three-justice bench of the NSW Court of Criminal Appeal (NSWCCA) determined in August 2025, that Ko was wrongly convicted, as the sentencing judge, on directing the jury as to what should have been a two-step process to ascertain guilt, had rather considered the first element as the only step needed, and therefore, left the second element unaddressed.
The NSWCCA then remitted the case back to the NSW District Court for retrial, while the Crown went on to seek special leave to appeal this judgment to the High Court of Australia, which was granted on 4 December 2025.
The contentious conviction
A NSW District Court jury found Ko guilty on one count of attempting to import a commercial quantity of two border-controlled substances under, sections 11.1, 307.1(1) and 311.1(1)(f) of the Criminal Code Act 1995 (Cth).
Section 307.1(1) of the Criminal Code contains the offence of importing a commercial quantity of a border-controlled substance. This crime carries a maximum penalty of life imprisonment.
Schedule 2 of the Criminal Code Regulations 2019 (Cth) contains the various quantities that make up the commercial and marketable quantities of all border-controlled drugs. A commercial quantity of methamphetamine is at least 750 grams, while phenylethylamine has the same quantity limit, as it is prosecuted as an amphetamine analogue, or as a substance similar in effect to amphetamines.
As the drug importation was not a success, Ko’s conviction also relied on the inchoate offence of ‘attempt’, contained in section 11.1 of the Criminal Code Act. A criminal offence accompanied by the incomplete offence of attempt results in the defendant facing the same maximum penalty for having unsuccessfully tried to perpetrate the offence, as when the crime has been carried out successfully.
For Ko’s conviction, the prosecution also relied upon the procedural mechanism within section 311.1(1)(f) of the Criminal Code, which allows for two different border-controlled substances to be considered together under the same count.
Following the jury’s finding of guilt, NSW District Court Judge Justin Smith then sentenced Ko to 6 years and 6 months prison time, with non-parole set at 3 years and 11 months.
Overturned on appeal
Ko appealed his conviction to the NSWCCA in August 2025. On appeal, Justice Julie Ward outlined that for the Crown to find a defendant guilty of drug importation three elements must be shown beyond a reasonable doubt, yet Judge Smith had instead conflated the two mental elements within this process that reveal guilt, so that the first of these elements had only been raised to the jury.
The first element that must be made out to prove the offence of drug importation is that the defendant intentionally imported a substance, and this can involve, as suggested in Ko’s case, importing a package when being aware of “a real and significant chance” that drugs were inside it. The second element to this offence is that the substance was a commercial quantity of a border-controlled drug.
The third element to be shown for the offence of drug importation to be made out is that the defendant recklessly or intentionally determined to import the package, after becoming aware of the potential for it to contain border-controlled drugs, and then the defendant “nevertheless persisted” with the importation of the suspect consignment.
The two mental elements involved in the three offence elements are being aware of “a real and significant chance” of drugs being involved and that the individual ‘nevertheless persisted’ on importation.
A miscarriage of justice was found made out on appeal, as the sentencing judge had, in summing up, referred to the two mental elements that had to be established to find guilt, but in his explanation, he only referred to the first element and how it was to be shown, and he then proceeded as if both elements had been made out.
Special leave to appeal
The Crown then appealed the NSWCCA outcome to the High Court in March, based on the sole ground that it had been in error in finding that the “judge had misdirected the jury” by failing to explain that not only did it have to prove beyond reasonable doubt that he was “aware of a real and significant chance” of importing drugs, but further, that he then “nevertheless persisted” in doing so.
During the trial, the Crown argued that Ko was the importer, as while Yang was the boss of the operation, the defendant had dealt with the logistics. The Crown further argued that Ko’s provision of false details when arranging the shipment tended to reflect guilt. The defence, however, argued that Yang had betrayed Ko, and no evidence had proven beyond doubt that he’d been aware of the drugs.
Counsel for the defence was instructed by Sydney Criminal Lawyers. In the High Court, the defence relied upon authorities that included the 1987 High Court case Kural versus The Queen and the 2017 High Court case Smith versus The Queen; The Queen versus Afford. These authorities had also been raised during the NSWCCA proceedings.
In Kural, the court established that intention to import border-controlled drugs can be established when the prosecution shows that the defendant was “aware of a significant or real chance” that drugs were being imported into the country as part of a shipment they were organising, and they “nevertheless persisted” in continuing with the consignment.
The High Court took this one step further in 2017’s Smith and Afford, when it found that if it is shown that a defendant had been “aware of a significant or real chance” that an illegal substance was within a shipment and the individual “nevertheless persisted” in importing it, then it can be inferred from these circumstances that the defendant did intentionally import the border-controlled drugs.
In terms of Judge Smith’s direction in Ko’s trial, the High Court found he’d been correct in having directed the jury that if it was found beyond reasonable doubt that Ko had imported the consignment on knowing there was “a real or substantial chance”, then they should not draw an inference that this was the case, unless it was the only possible inference able to be drawn.
But Smith’s directions failed to provide the second required step relating to the jury considering and going on to find that given Ko’s understanding of the “real or substantial chance” that he then “nevertheless persisted” in importing the consignment.
This meant that the jury had been told that it was permitted to find Ko guilty based merely on the understanding of his believing that there was “a real or substantial chance” that drugs were contained in the mixer consignment, without any consideration of his “nevertheless” persisting with the operation.
The jury, therefore, falsely found Ko guilty of the offence and the Crown’s sole ground of appeal was not made out.
The orders of the day
These findings resulted in the High Court case The King versus Ko being dismissed on 12 August 2026. The ruling was handed down by High Court Chief Justice Stephen Gageler and Justices Michelle Gordon and Robert Beech-Jones, while Justices James Edelman and Jayne Jagot concurred with their findings, whilst both providing their own separate reasons.
Justice Jacqueline Gleeson and Simon Steward dissented from this position, however, finding that the sentencing judges’ directions to the jury had been adequate within the context of Judge Smith’s full summing up.
