Conflict of interest allegations involving the Darwin Waterfront Corporation were referred to the Northern Territory parliament's public accounts committee by Opposition Leader Selena Uibo in May.
She said under parliamentary privilege that among the claims was the "alleged creation of a made-up, part-time job for Mr Sam Burke", the waterfront corporation's deputy chief executive.
Mr Burke, the husband of Chief Minister Lia Finocchario, has worked at the corporation since 2016.
Ms Uibo said his the role was "reportedly unadvertised" and allegedly resulted in a $60,000 salary increase through a temporary higher duties allowance.
The allegations were too serious and the public money involved too significant to be "swept under the rug", she told parliament.
The waterfront corporation is a statutory authority set up by the NT government to control one of the Top End's most popular recreational precincts, including a wave lagoon, beaches, parks, restaurants and bars.
Ms Uibo also referred to reports of public service rules being repeatedly breached, roles not advertised, promotions bypassing merit-based reviews and job evaluation processes ignored to benefit certain individuals.
But Tourism Minister Marie-Clare Boothby said the Public Accounts Committee had found there was "absolutely no case to answer", with the public now questioning Ms Uibo's integrity and judgement.
The Public Accounts Committee has five members, with a government majority of three.
"The current leader of the opposition used parliamentary privilege to smear public servants with baseless allegations," Ms Boothby said in a statement on Tuesday night, saying the committee decision was unanimous.
She said Ms Uibo owed public servants and all Territorians an apology after making "baseless claims".
"I dread to think how much taxpayer's money was wasted by the opposition slinging mud at public servants," she said.
The waterfront corporation has denied any wrongdoing, saying in a statement it was audited annually by the NT auditor-general who had found "no evidence to support any finding of financial or governance misconduct".
In response to the committee's ruling Ms Uibo said she held the NT public service in the highest regard and always treated public servants with the utmost respect.
She said she referred the matter to the committee to resolve issues raised publicly and that voters continued to raise with her and her team.
"I would not be doing my job as opposition leader if I didn't raise questions on behalf of territorians," Ms Uibo said.
"The community expect the government to be open and transparent and I will continue to hold them to this."