The case of a getaway driver jailed for 20 years for killing Melbourne career criminal Victor Peirce has been referred to the appeals court over a potential miscarriage of justice involving his lawyer, Nicola Gobbo, also known as “Lawyer X”.

Victoria’s attorney general, Jill Hennessy, has used her powers to refer Faruk Orman’s matter to the court of appeal for hearing.

She said it was not necessary to wait until the final report by the royal commission into the management of police informers, given the volume of material already available about Gobbo’s conduct in relation to Orman.

Orman was jailed for 20 years in 2009, with a minimum of 14 years, after a supreme court jury convicted him of murdering Peirce in 2002.

Peirce was a career criminal who was originally charged but later acquitted over the murders of police officers Steven Tynan and Damian Eyre in Walsh Street at South Yarra in 1988.

Peirce had been sitting in his car outside a Telstra shop in Port Melbourne waiting to buy drugs when he was shot dead.

He was shot by hitman Andrew “Benji” Veniamin, who was himself shot dead two years later, while Orman was convicted for his role for helping plan the execution and driving the getaway car.

Hennessy said she received a petition for mercy on Orman’s behalf in February. His lawyers provided detailed submissions and evidence, prompting her to seek independent legal advice.

“Based on the material provided by Mr Orman’s lawyers, I am satisfied there is credible evidence that there may have been a miscarriage of justice in Mr Orman’s case arising from Nicola Gobbo’s conduct and use as a human source by Victoria Police,” Hennessy said on Wednesday.

The royal commission is examining cases affected by the conduct of Gobbo and the extent those cases may have been affected.

The inquiry is also considering the conduct of police who recruited and managed her as an informer and its final report is due in July 2020.