Commissioner Lynelle Briggs said Mr Tracey died in California, where he was being treated for cancer that was diagnosed seven weeks earlier.

“[Mr Tracey] was experienced. He was wise. He was admired. He knew the law like the back of his hand. He was prepared to take a punt if it meant we got the best outcome," Ms Briggs said.

"His kind words to our witnesses after their presentations gave them comfort and let them know that they had been heard. His gentle guidance and direction to royal commission staff always helped, and made our collective lives so much easier."

The new chairman of the royal commission, Tony Pagone, QC, said Mr Tracey's "work on this commission has … been solid, selfless and significant".