Mark Anthony Dumenil, 52, was sentenced to 11 years’ imprisonment in February 2023 after a jury found him guilty of one count of attempting to possess a commercial quantity of imported drugs.

The Brisbane Court of Appeal on Tuesday found that Dumenil had not faced a fair trial as the jury likely convicted him using evidence against his co-defendant.

Justices Debra Mullins, David Boddice and Peter Callaghan took a few minutes to consider their judgment before ordering Dumenil’s conviction be overturned.

Justice Mullins said the court would publish its reasons at a later date but earlier said she was concerned about what the jury was told.

“This is a question of inadmissible evidence being before the jury,” she said.

On January 8, 2018 the Australian Border Force found 26.5kg of pure cocaine in 99 packages hidden in the roof of a shipping container that had arrived in Brisbane from Colombia.

Dumenil faced trial alongside Hashanth Arjuna Kulatunge, 53, as both Melbourne business owners were accused of flying to Brisbane to meet the shipping container at a warehouse.

Dumenil’s barrister Jakub Lodziak told the appeal that the jury had not been sufficiently instructed about Kulatunge’s claim that Dumenil helped him retrieve the cocaine.

“It was not conceded that (Dumenil) even knew about the hoard of cocaine. There were no fingerprints or DNA. The only evidence linking him directly was (Kulatunge’s) statement,” Mr Lodziak said.

Crown prosecutor Clare O’Connor said an error was made at trial but there was other evidence against Dumenil, including covertly recorded audio.

“The strength of the case itself is overwhelming,” she said.

Justice Mullins said a message needed to be sent about oversights that could have been corrected during the original trials.

“We get a number of appeals where it is quite apparent that trial counsels’ eyes glazed over as the judge (summarised the evidence for a jury) and they really have to remain alert,” Justice Mullins said.