The CFA has blocked a Freedom of Information request from the firefighters' union for response time data for a group of volunteer brigades. The request was denied on the grounds the information would "likely cause a loss of confidence in the service".

It comes as Commissioner for Children and Young People Bernie Geary said he would not release his investigation into the sexual exploitation of children in residential care ahead of the November poll because he did not want the inquiry to be rushed or politicised.

"I don't want to make this review part of the machinations of an election campaign so it is important it takes its normal course and it will be finished by the end of the year."

He said people had approached him and suggested the inquiry could be of interest before an election.

"I think that would be disrespectful to young people," he said.

The United Firefighters' Union request to the CFA was denied because the information would "expose the CFA to unreasonable disadvantage".

"The documents contain information relating to core business of this agency and disclosure of the documents could be misleading, lead to misrepresentations and would be likely to cause a loss of confidence in the service provided by the agency," the ruling said.

On Monday The Age reported that Ambulance Victoria had blocked freedom of information requests on response time for cardiac arrests because it may be misunderstood and cause Victorians to lose faith in the service.

And Police Chief Commissioner Ken Lay has also decided to delay the release of quarterly crime stats until after the election, conceding he was in "a no-win situation".

Mr Lay said he was going to release the data without comment just three days before the election but advice from the state's ombudsman changed his mind.

"(She said) without an independent body to mitigate the risk it is reasonable and indeed sensible to delay the release of statistics by a few days to avoid any risk of politicisation," Mr Lay said.

Premier Denis Napthine on Monday denied any cover-up on the police and ambulance data, saying the Coalition had released more data about crime, health and ambulance services than any other government in Victoria's history.

"We are an honest, open, transparent government providing the best information to the people of Victoria," he said.

"This is not a political decision but I welcome their decision."

UFU secretary Peter Marshall said the public was entitled to know whether the CFA was meeting its target times for responding to emergency calls.

"The Napthine government seems intent on keeping secrets from Victoria - the business case for the East-West Link, ambulance response times, and now CFA response times."

The union has appealed to the FOI Commissioner.

Shadow Emergency Services Minister Wade Noonan said spending millions of dollars on government advertising while suppressing basic performance data about our emergency services was a very low act.

"Denis Napthine would rather safeguard his government than be open about his community safety track record," Mr Noonan said.

Emergency Services Minister Kim Wells said the FOI matter was dealt with "independently and directly" by the CFA. The CFA said as the matter was now with the FOI commissioner it could not comment.