The High Court was wrong to permanently stay the drug trafficking trial of a man from Brazil, after the judge applied incorrect legal principles to exclude some text messages from the suspect’s phone from the evidence.

This is according to a written ruling by the Court of Final Appeal on Monday, which said the trial judge, Audrey Campbell-Moffat, had erred in several legal principles during the proceedings last year.

The case centered on a man who flew in from Sao Paulo via Zurich on September 10, 2019. Customs officers at Hong Kong airport found more than 3,300 grammes of cocaine in his suitcases.

The man denied knowing the drugs were hidden in the luggage, and claimed a woman he met online asked him to bring the cases to Hong Kong and told them they contained confidential documents.

Customs officers took photos of WhatsApp messages from the defendant’s phone and submitted them as part of the facts admitted by both sides to the jury trial.

But Justice Campbell-Moffat questioned the admissibility of the photos and ordered a “voire dire procedure” – a separate hearing held in the absence of the jury within the trial – to handle the matter.

The messages and other references to them were eventually removed or redacted from the admitted facts after she ruled they were inadmissible.

The defendant later applied, and was granted, a permanent stay of the proceedings, on the grounds that he could not receive a fair trial without the WhatsApp evidence. He subsequently left Hong Kong while on bail.

In its ruling on Monday, the top court said the trial judge should not have held the voire dire hearing, and thus was wrong to use its outcome as the basis to stay the prosecution.

The Court of Final Appeal said the prosecution is now free to list the trial before another judge of the Court of First Instance, who may then issue a warrant of arrest against the suspect if he refuses to return to face trial.