Former chauffeur Gordon Wood claims he was wrongfully convicted of the murder of model Caroline Byrne due to a biased and flawed police investigation that relied on evidence from a witness with irrelevant expertise.

Mr Wood, a one-time chauffeur for high-profile stockbroker Rene Rivkin, was charged over his former girlfriend's death after her body was found at the base of notorious Sydney suicide spot The Gap in mid-1995.

He was found guilty in 2008 and spent several years behind bars but the conviction was quashed in 2012 and Mr Wood is now pursuing damages against the state of NSW.

Mr Wood will be called as the first witness likely later this week.

His lawyer, Bruce McClintock SC, on Monday opened the case in the NSW Supreme Court and claimed the "flawed and biased" investigation led to a miscarriage of justice.

"It was always intended to find my client was guilty of murder, not to get to the actual truth," Mr McClintock said.

The evidence of retired University of Sydney physicist Associate Professor Rod Cross was heavily criticised.

Mr McClintock accused the professor of being "prepared to fabricate evidence" and harbouring a motive to see Mr Wood convicted because he was writing a book about how physics contributed to the police investigation.

"It's breathtaking that this man could ever have been put up as some form of independent expert," the lawyer told the court.

Mr McClintock said it was "astounding" the professor admitted, in the Court of Criminal Appeal, he was aware that a photograph of the cliff top was taken in 2003 despite the jury being told it was taken in 1995.

Mr McClintock told the court the prosecution and police took Prof Cross on as a member of their team and were "directly liable for his activities".

The professor had no relevant expertise because his background was in plasma physics, or the behaviour of high-temperature gasses, Mr McClintock said.

"How that qualified him to give evidence about the behaviour of bodies when they're thrown from cliffs is very hard to see."

The court heard during the month before her death, Ms Byrne presented to her then-GP with severe depression and did not disclose that she had previously attempted suicide.

Her mother died from an overdose in 1991 and Ms Byrne made a similar attempt in 1992.

Mr McClintock described Ms Byrne's organic depression and said while hers was a "terribly sad story" the investigation and subsequent prosecution of Mr Wood was a "sorry saga".

Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14 or Suicide Call Back Service 1300 659 467.

AAP

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