A former federal ombudsman will stay in charge of an inquiry into a complaint about public service commissioner John Lloyd, as the official responsible for investigating him commences her new role.
Professor John McMillan is conducting an independent investigation into an allegation Mr Lloyd breached a code of conduct, after the former acting merit protection commissioner Mark Davidson engaged the ex-ombudsman for the probe.
While new permanent merit protection commissioner Linda Waugh started her role on June 25, a week after the inquiry began, her office has confirmed she won't take over the investigation.
The probe into the complaint may remain unfinished when Mr Lloyd leaves his $706,000-a-year role on August 8, as the Office of the Merit Protection Commissioner could only say on Tuesday it would "be conducted with as much expedition as a proper consideration of the matter allows".
Under public service legislation there is no power to investigate Mr Lloyd, who is responsible for upholding standards of integrity and conduct in the Australian Public Service, once he departs the agency.
Mr Davidson was acting merit protection commissioner when he received the complaint in January, but his substantive role was in the agency Mr Lloyd led.
He has said he initially decided not to act on the allegation about Mr Lloyd, expecting the merit protection commissioner position to be filled permanently within weeks.
When a permanent merit protection commissioner was not appointed by March, he said he dealt with his conflict of interest by contracting former Attorney-General's Department secretary Robert Cornall to advise on whether to commence an inquiry.
Mr Cornall in April recommended a probe into the complaint and Mr Davidson decided to commence one, engaging former Commonwealth ombudsman, acting NSW ombudsman and Australian information commissioner Professor McMillan to conduct the investigation.
Professor McMillan will report to Ms Waugh when finishing the inquiry.
When asked by Labor senator Jenny McAllister at a Senate estimates hearing last month whether Ms Waugh would conduct the investigation upon commencing her role, Mr Davidson said it was a matter for the new merit protection commissioner.
Mr Lloyd in January chaired a panel recommending candidates for the role, but was yet to learn Mr Davidson had received a complaint when the panel conducted interviews and recommended appointees.
The public service commissioner, whose term was due to expire in December 2019, abruptly announced last month he would resign but denied the timing was influenced by a possible investigation. His agency said then he had "for some time" considered departing before his term as commissioner ended, and Mr Lloyd later told senators he had felt it was time to resign after a long career.
His announcement came after mounting pressure over his connection to right-wing think tank the Institute of Public Affairs, and revelations in May he faced a possible inquiry.
Mr Lloyd's links to the think tank came under growing scrutiny after it was revealed at a Senate estimates hearing in October he sent an email to a member of the IPA with an attachment showing what he described as "generous" provisions in public service enterprise agreements.
He has rejected suggestions he gave it special access and research.