Johannesburg – An expert witness from Australia has told the commission investigating the deadly 2015 M1 bridge collapse that he approached his modelling with an open mind and sound judgement, the labour department said on Friday.In a statement issued on Friday, the department said Form-Scarf expert witness and mechanical engineer Gary Farrow said: "I did not prejudge evidence in view of evidence on site. "My mandate was configuration of the temporary structure and ascertains the causes of collapse."Farrow took the stand on Tuesday and told the commission that, although he had limited access to contracts between Form-Scaff and Murray & Roberts, his "analysis of the fatal site disproves insinuations that he was biased in favour of his employer", according to department spokesperson Mokgadi Pela. Pela said Farrow had been accused by Murray and Roberts of being biased in his modelling, which he allegedly denied. Two killedHe said during the inquiry, Murray and Roberts said it wanted all inputs and outputs that were modelled. After the four day inquiry, Farrow was ordered to return to South Africa on August 29 to provide certain crucial evidence required by Murray and Roberts, the principal contractor, said Pela.The structure collapsed onto the M1 at Grayston Drive around 15:30 on Wednesday, October 14.The driver of a minibus taxi and a man in a Toyota Fortuner were killed and 19 people were injured. The scaffolding that collapsed was a support structure for what was intended to be a pedestrian and cycle bridge connecting Alexandra and Sandton.