The NSW corruption watchdog is facing claims it had neither the authority nor the evidence to find former premier Gladys Berejiklian was corrupt due to her secret relationship with a fellow MP.
In June, the Independent Commission Against Corruption found Ms Berejiklian engaged in serious corrupt conduct by breaching public trust and refusing to report her then-lover, Liberal MP Daryl Maguire.
Ms Berejiklian is challenging the findings in the NSW Court of Appeal.
In her court summons, she argued the corruption findings were "illogical or irrational" because ICAC also said there was insufficient evidence to prove the accusations to the criminal standard.
The commission stopped short of recommending criminal charges against the 55-year-old former premier, citing "formidable" obstacles to prosecution.
Ms Berejiklian also claimed former judge Ruth McColl, who was appointed assistant commissioner to help with the inquiry, did not have the authority to prepare the ICAC report.
Originally retained as assistant commissioner until October 31, 2022, ICAC extended the time she had to work on the report as a consultant until the 688-page document was released in June this year.
Because of her change in position, Ms McColl did not have any authority to compile the report and release it, Ms Berejiklian's summons argued.
Findings the former premier had a private interest in or was influenced by her personal relationship with Maguire were "not supported by any probative evidence", it added.
Ms Berejiklian denies that the relationship amounted to a conflict of interest or that she breached public trust by failing to declare it.
ICAC found Ms Berejiklian breached public trust with her involvement in funding decisions for two proposals advocated for by Maguire, the Wagga-based Australian Clay Target Association and the Riverina Conservatorium of Music.
Between 2016 and 2018, when she was treasurer and then premier, Ms Berejiklian was involved in approving or supporting allocations of $5.5 million for the clay shooting club and $10 million for the conservatorium.
In her court challenge, Ms Berejiklian claimed that ICAC exceeded its authority by making findings relating to those two proposals.
"The assessment of the merits of such decisions, and whether they are in fact in the public interest, is the exclusive province of the elected representatives responsible for them," her summons said.
The matter will next come before the NSW Court of Appeal on October 9.
ICAC's June report also made numerous findings about Maguire's serious corrupt conduct involving enterprises unrelated to Ms Berejiklian, including his use of his public office to enrich himself.
Maguire resigned from parliament in 2018 in the wake of the inquiry.
He is facing criminal charges for his alleged involvement in a visa fraud scheme and allegedly misleading statements to ICAC over his business dealings.
Both matters are currently before the courts.
