A subsidiary of construction giant Grocon says a fine of $250,000 would reflect the part it played in the fatal collapse of a brick wall in Melbourne.
The company's defence barrister Ross Ray says construction faults in the wall were not known until after it collapsed and because it was built in accordance with a building permit, there was no need to recertify it.
"No one questioned the integrity of the wall," Mr Ray told a plea hearing on Thursday.
Grocon Victoria Street Pty Ltd has pleaded guilty to one count of failing to ensure a safe workplace over the collapse but says it relied on the expertise of signing company Aussie Signs Pty Ltd, which installed advertising hoarding on the wall.
It faces a maximum fine of $305,000.
Teenage siblings Alexander and Bridget Jones, of Melbourne, and Frenchwoman Marie-Faith Fiawoo, 33, were killed when a 15-metre long section of the structure fell onto Swanston Street in March last year.
Prosecutors say the hoarding placed on the wall by Aussie Signs at the request of Grocon Victoria Street increased the risk it would collapse but did not cause it.
Mr Ray says Grocon Victoria Street recognises it should have done more but believed itself to be a client of Aussie Signs and relied upon its expertise.
"We are a client, and a client of a company that was regarded as appropriately expert," Mr Ray told Melbourne Magistrates Court.
He also said because the site was a vacant lot and not a building site, certain safety procedures were not triggered.
"A fine in the range of $250,000 reflects the level of the breach."
Prosecutor Greg Lyon, for the Victorian WorkCover Authority, said the company had responsibilities in relation to the wall.
"Grocon Victoria Street failed to ensure Aussie Signs checked the integrity of the wall," Dr Lyon said.
He said the company was part of a large, well-resourced construction group and a large number of people were exposed to the risk the wall would collapse.
Grocon Victoria Street's actions were not causative, Dr Lyon said, but the foreseeable consequences of the breach of the Occupational Health and Safety Act had to be taken into account.
Magistrate Charles Rozencwajg will sentence Grocon Victoria Street on Friday.
