Attorney-General Christian Porter has criticised his Labor opponent in the WA seat of Pearce over campaign posters showing Kim Travers in her police superintendent's uniform.
WA Police Commissioner Chris Dawson asked for the posters to be removed.
Mr Dawson pointed out that Ms Travers was no longer a serving police officer, having resigned to stand as an election candidate.
Mr Porter described the attempts to politicise the force as "totally inappropriate".
"I raised a concern about this issue with the WA police commissioner last night," Mr Porter said in a statement as voting continued on Saturday.
"It is a well-known requirement that where WA Police officers are candidates for political election, they may not use images or vision of themselves in uniform in any campaign material or context.
"The independence of the police force is something that should always be protected and should always come before any individual advantage."
A Labor campaign spokesperson defended Ms Travers and said Labor was proud to have her running in Pearce.
"Kim Travers is a decorated police superintendent who served the community as a member of the WA Police for 29 years," the spokesperson said.
"Kim Travers and Labor are focused on delivering real change to the people of Pearce."
Mr Porter holds Pearce by 3.6 per cent and is facing a tough challenge from Labor.
His seat is one of a number in the west that could fall to the ALP though he told reporters he was quietly confident of hanging on.