The Queensland police officer who booked the Police Commissioner's wife for an alleged traffic infringement was not interviewed as part of a Crime and Corruption Commission (CCC) assessment into why the ticket was later withdrawn, the ABC can reveal.

Key points: The CCC investigated the matter after Ian Stewart's wife's fine was withdrawn

The CCC investigated the matter after Ian Stewart's wife's fine was withdrawn The corruption watchdog confirmed it did not interview the officer who issued the ticket, only the officer in charge

The corruption watchdog confirmed it did not interview the officer who issued the ticket, only the officer in charge The State Opposition Leader said it seemed highly unusual

Late last week, the CCC found in response to complaints that there was "no evidence to raise any reasonable suspicion of corrupt conduct or police misconduct" surrounding the withdrawal of the infringement notice issued to Carol Stewart.

"The CCC did not identify any close personal or professional relationship between the officers involved in this matter and the Commissioner of Police [Ian Stewart]," it said.

As revealed by the ABC last week, Ms Stewart was issued the ticket last month by a senior constable after allegedly failing to stop at a stop sign.

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She later wrote to the officer in charge of the local station questioning the infringement notice, and the officer agreed to withdraw it.

"The letter revealed a detailed knowledge of the relevant statutory provisions and procedures relating to the issuing of infringement notices, consistent with Mrs Stewart's long career as an employee of the Department of Transport and from her earlier career as a police officer," the CCC found in its assessment.

"The officer who made the decision wrote to Ms Stewart advising of the decision to withdraw the infringement notice. In this correspondence, it is clearly articulated on what grounds the decision was made."

As part of its assessment, the CCC interviewed the officer in charge but confirmed to the ABC that it did not interview the officer who issued the ticket.

"The allegations of possible corrupt conduct or police misconduct assessed by the CCC related to the withdrawal of the infringement notice by the decision maker and any potential involvement of the Commissioner of Police," it said.

"The issuing officer was not the decision maker in this matter. The CCC notes this officer is currently on leave."

'It seems highly unusual': State Opposition Leader

State Opposition Leader Deb Frecklington, who lodged one of the complaints to the CCC, said "it seems highly unusual that the CCC didn't speak to all parties involved, including the officer who issued the ticket".

"Most Queenslanders don't have their tickets ripped up, so a thorough investigation is appropriate. Annastacia Palaszczuk and her Police Minister have failed to adequately answer questions on this matter, meaning a lot of unanswered questions remain," she said.

The CCC said the officer who issued the ticket was not under investigation.

"If new information is received by the CCC that may be relevant to this matter, it will be assessed independently to determine if any further action by the CCC is warranted," it said.

The Queensland Police Service said Ms Stewart had "exercised her legal right" in seeking for the ticket to be withdrawn, saying it was a process open to "all members of the public who have been issued an infringement notice".