Casper Louis of Salamua, Morobe Province pleaded guilty on March 7 for his involvement with others in the Maybank robbery, where K5.9 million was taken by G4S security guards during transportation to the Central bank.
No trial was conducted in his case because he admitted to the allegations. He will now return to court for submissions on sentence.
Louis is among the other four men who were employed by G4S at the time of the offense.
The others are Paul Steven, Gelison William, Hubert Korede and Stewart Korina. Samson Banaso was not an employee of G4S.
A trial was conducted against these five men after they pleaded not guilty to the offense.
They were convicted for armed robbery on 13 April.
Steven, William, Korede, Korina, and Banaso will return to court on May 22.
The Probation Service has been given until then to complete their means assessment reports and pre-sentence reports before the court can decide on their appropriate penalty sentence.