Eamonn Harrison, from Mayobridge in Newry, County Down, Northern Ireland, appeared at the High Court in Dublin on Friday in relation to a European Arrest Warrant seeking his extradition to the UK.
The 23-year-old is wanted for his alleged role in transporting the trailer in which the bodies of eight women and 31 men, all Vietnamese nationals, were found on an industrial park in Grays, Essex, in the early hours of October 23.
Two of the dead were only 15 years old.
The court previously heard that Harrison had been accused of 41 offences – 39 counts of manslaughter, which carries a maximum sentence of life imprisonment, one human trafficking offence, and one count of assisting unlawful immigration.
He is alleged to have driven the container to the port of Zeebrugge in Belgium, and later signed the shipping notice for it.
The 31 men and eight women are believed to have paid people traffickers for their clandestine transit into England.
British police have charged 25-year-old Maurice Robinson, also from Northern Ireland, with 39 counts of manslaughter and conspiracy to traffic people. They say he drove the cab of the truck to Purfleet, England, where it picked up the container, which had arrived by ferry from Zeebrugge.
Justice Donald Binchy on Friday said after hearing very comprehensive arguments from both sides, he had decided to approve Harrison’s extradition.
He said there was nothing in law to preclude the surrender of Harrison.
Justice Binchy’s judgement will be published in full next Monday after the judge said it would not be helpful for him to try to summarise his decision to the court.
Defence counsel Tony McGillicuddy said he will decide whether to appeal after reading the full judgement next week.
Harrison, wearing glasses, a purple jumper, multi-coloured shirt and blue jeans, showed little emotion when the judge granted the order.
The judge said he considered making the order today, however he deferred his decision to allow the defence time to consider an appeal.
The judgement runs to some 50 pages, and the judge said he wanted to give the defence team time to consider it.
“It would not be fair to put such pressure if the respondent chooses to appeal,” he added.
McGillicuddy said that was a “better position to adopt”, adding that he had a number of other concerns to consider – including Brexit.
Harrison was remanded into custody and will appear in Dublin’s High Court on February 4.