Allegations that the Australian Competition and Consumer Commission was unjustly harming the reputation of businesses by investigating public allegations against them were rejected today by ACCC Chairman, Professor Allan Fels.

The claims were made by Qantas today.

"It is the ACCC's duty to investigate claims of anti-competitive conduct, including collusion and price-fixing", Professor Fels said.

"Our role is to protect the public from anti-competitive behaviour. The mere fact we are investigating can attract criticism from those being investigated.

"Mr Dixon complains that there has been publicity about complaints regarding Qantas' activities. These complaints, from business rival Virgin Blue, were heavily publicised by that business rival, not the ACCC. The ACCC has confirmed the obvious – it is investigating the complaints. The allegations made are still under investigation.

"The ACCC does not normally confirm or deny if any investigation is under way.

"However, Qantas regularly makes efforts to attack the ACCC privately as well as publicly, such as in today's speech.

"In the case of last week's 'walk-ins' on oil companies, publicity about the ACCC's actions was inevitable as the whistleblower had contacted The Daily Telegraph via letter outlining her main allegations. The Daily Telegraph published them.

"Further, with around 90 officers moving on eleven sites, it would have been impossible to conduct the 'walk-in' in total secrecy.

"Mr Dixon could be underestimating the Australian public. The public knows the difference between an investigation, an allegation and a court verdict of unlawful behaviour.

"I reject his criticism and the ACCC will continue to do its work without fear or favour".