A former senior public servant is taking South Australia's integrity body to court over a botched prosecution in which investigators infringed on the sovereignty of a foreign country.
John Hanlon, the former chief executive of Renewal SA, was in 2020 accused by the state's Independent Commission Against Corruption of fraudulently claiming private travel expenses - including airfares, accommodation and meals - during a trip to Germany.
But the charges against Mr Hanlon were dropped before the case went to trial.
In a pre-action claim lodged with the state's Crown Solicitor, lawyer Matthew Selley alleged ICAC's pursuit of his client destroyed his career and caused him "significant psychological harm", entitling him to damages.
"We contend that the ICAC investigation was fundamentally flawed from the outset in several ways," he said.
Mr Selley contends the corruption watchdog acted improperly by handing evidence to prosecutors without disclosing investigators had breached German law by taking affidavits from witnesses there without authority, making the evidence inadmissible under Australian law.
"Mr Hanlon maintains that, had the (Director of Public Prosecutions) known the true state of affairs, Mr Hanlon should never have been charged," he said.
"The apparent concealment by ICAC officers of what they had done from both the DPP and Mr Hanlon set in train a process which destroyed his career and caused him significant psychological harm."
Mr Hanlon has consistently denied any wrongdoing and no findings of guilt have been made against him.
ICAC Inspector Philip Strickland found in a review of the matter investigators' failure to obtain the permission of local authorities "constituted an infringement of Germany's sovereignty".
"The conduct also had the potential to cause diplomatic embarrassment to Australia or South Australia," he said.
Mr Hanlon's extensive career, which culminated in his appointment as head of SA's public development agency, was abruptly halted when ICAC officers raided Renewal SA offices in September 2018.
He has not worked since, his lawyer says.
ICAC Commissioner Ann Vanstone has acknowledged "substantive errors" in its investigation and agreed to implement changes to its processes, including more staff training and better record-keeping.
Although ICAC bungled the process of the probe, Mr Strickland found the initial decision to investigate Mr Hanlon was "reasonable and appropriate".