A Maltese-Australian undergoing a corruption inquiry in New South Wales this morning heard one of the main witnesses testify to his integrity.

Joseph Camilleri, former maintenance manager of RailCorp, is being investigated for requesting and receiving loans from contractors he supervised as part of his duties. He was dismissed by RailCorp last year when the company discovered he had taken loans from contractors and employees, including the head of RailCorp himself.

He had sought the funds to pay off his daughter’s debts.

Kevin McCarthy, general manager of infrastructure company UGL , which had a a $1.4 billion train maintenance contract with RailCorp, said he had lent A$428,000 to Camilleri.

Nicholas Polin, prosecuting, asked Mr McCarthy how Mr Camilleri could impartially oversee the maintenance contract in the context of the loan.

Mr McCarthy said he had known Mr Camilleri for over 20 years. "I have witnessed Joe using his impartiality in every other decision that I had made," he said. "I think there is a clear distinction between the personal loan and business," he said. "I believe there were no ramifications in a business sense."

Mr Camilleri’s sister, Carmen Attard, has also been accused of using her post at the Department of Family and Community Services to solicit funds for her niece.