Townsville mayor Troy Thompson formally resigned on Friday after being suspended for 12 months on full pay by the Queensland government in November 2024.
Mr Thompson won the mayoralty in March 2024 after claiming to have served in the army for five years including at Swanbourne, the elite Special Air Service base in Western Australia.
After questions were raised about his service, Mr Thompson said he had in fact served three years in the Army Reserve, mostly in catering.
He blamed a history of "100-plus" concussions for his confusion over the matter.
His resignation comes a week after he was issued a show-cause notice, following a briefing by the Crime and Corruption Commission (CCC) to Local Government Minister Ann Leahy on ongoing investigations.
On Friday, the CCC said an investigation, close to conclusion, into several allegations relating Mr Thompson would continue despite his resignation.
"Until such time as the investigation is finalised, the Crime and Corruption Commission does not propose to comment further," it said.
Ms Leahy has described the issues related to Mr Thompson as "a lengthy saga for the people of Townsville".
But with Mr Thompson vowing to run in the forthcoming by-election, she said she was unable to shed light on the contents of the show-cause notice as the commission had prevented her.
"The people of Townsville would want to know that information before they go to the polls, and it is my view that they deserve that information," she told reporters.
"The CCC has specifically restricted me from releasing that information."
She deflected questions regarding why she was unable to release the information, saying it was a matter for the commission.
Ms Leahy instead said the contents of the show-cause notice had been provided directly to Mr Thompson, encouraging all candidates to be "open and transparent".
Townsville is home to more than 15,000 Australian Defence Force personnel.
Mr Thompson had resisted calls to stand down before finally resigning on Friday, blaming the state government for its "political overreach".
He used his resignation as a re-election bid on social media, confirming he would recontest the mayoralty.
"Let me be absolutely clear about this. This resignation is not an admission of wrongdoing," Mr Thompson said in a video statement posted on Friday morning.
"It is a deliberate and principled stand to protect the democratic rights of the people of council - political interference has no place in our democracy.
"Only the community should decide who leads this city.Â
"I was elected by 53,956 people on a clear mandate, yet the premier and minister are attempting to use government bureaucracy to overturn that decision."
The by-election date is yet to be set but Ms Leahy said she hoped to make an announcement next week.
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