Motorists booked for speeding will not get away with breaking the law, a spokesman for the Police and Emergency Services Minister Peter Ryan has said.

On Monday, it was reported that 40,000 contested fines had been withdrawn because there were insufficient staff in the Traffic Camera Office to deal with the backlog.

Under the Infringement Act, if a request for a fine review is not dealt with within 90 days, not 45 days as previously reported, it must be withdrawn.

The issue was first mentioned on ABC Radio and was confirmed by the Community and Public Sector Union.

“Claims by Labor's union mates that 40,000 contested speeding fines are to be withdrawn are absolutely false," Mr Ryan's spokesman said.

“Victoria Police Assistant Commissioner Robert Hill stated at least three times yesterday that the allotted 90-day period for dealing with an appeal to a fine had not lapsed in any case. No fines have been withdrawn," he said.

“Independent Traffic Camera Commissioner Gordon Lewis has stated this morning that he has made his own investigations and is satisfied this is exactly the case."

CPSU state secretary Karen Batt raised concerns about the use of contractors in the public service, especially to deal with ethical and legal issues such as traffic fines reviews.

Six staff from labour hire company Tenix have been hired to join the Traffic Camera Office and are expected to be there until at least June, following staff cuts at the office.