Opposition transport spokesman Alistair Coe has called on the ACT government to release an expert review of Canberra's speed camera network completed last year.
The review into the effectiveness and impact of fixed speed cameras and their locations by the University of NSW Transport and Road Safety Research Centre cost taxpayers $163,000 and was commissioned in March 2014.
Researchers considered point-to-point and fixed cameras, how slowing drivers could cause accidents around speed camera locations and community attitudes to the network.
Two weeks after the report was commissioned, ACT Auditor-General Maxine Cooper slammed the government's management of the cameras in a separate report in March, finding no evidence they reduce speeding on territory roads.
Figures provided by the ACT government show 47,900 fines were issued to drivers on ACT roads in the year to March 2014. Most came from the 13 fixed and 13 red-light speed cameras.
The cameras netted more than $11.48 million in fines.
In September a Justice and Community Safety Directorate spokeswoman said the final UNSW report was being considered by the ACT government and would be released later in 2014.
Its release was also blocked under freedom of information rules in October, when the government said it planned to table the report in the Legislative Assembly this month.
Mr Coe said the failure to release the report in full suggested the government was concerned about its findings being made public.
"Following a strong of problems with ACT Labor's speed cameras, in March last year the government commissioned the University of NSW to conduct an evaluation of the ACT road safety camera program," Mr Coe said.
"Given the report cost $163,924 and was due to be submitted on June 28, 2014, the government should have already made it public. What is ACT Labor hiding here?"
Justice Minister Shane Rattenbury said the report was prepared within the planned budget.
"I recently took on the Justice portfolio and am in the process of considering the report," he said in a statement. "I plan on releasing the full report in the near future."