Brisbane City Council's Labor opposition has estimated tens of thousands of dollars of ratepayers' money would have flowed to Parakeelia, a controversial company with Liberal Party links, since 2009.

Federal Opposition Leader Bill Shorten described Parakeelia as a "scam" on Wednesday and called on the Auditor-General to conduct an investigation into the flow of money from the company to the Liberal Party's coffers.

"This looks like a Liberal Party washing machine turning taxpayer dollars into Liberal Party profits," Mr Shorten told reporters in Perth.

"(Prime Minister Malcolm) Turnbull needs to get off the fence and stop being in denial about the scam."