Yesterday, Scott Morrison told us that he knew better than the Treasury when it came to Labors housing affordability reforms.

Today, in Question Time, Mr Morrison said he knew better than the Productivity Commission despite initiating their inquiry - and its finding that the banks had been passing $500 million in costs to the taxpayer via interest deductibility in response to APRAs macroprudential measures.

SHORTEN: My question is to the Prime Minister: The Productivity Commission has found that the Government's intervention in the housing sector and I quote, "Led to a windfall gain for the banking sector. Up to half of this gain is in effect being paid by taxpayers as interest on loans is tax deductible. The Commissioner says the cost born by taxpayers was up to $500 million a year, does the Prime Minister agree or disagree?

MORRISON: Mr Speaker, I don't agree. I don't agree. No, I don't agree.

Then to top it all off, Mr Morrison then told David Speers on PM Agenda today that the Productivity Commission was wrong on their criticisms of the bank tax costing consumers.

Mr Morrison has had a terrible time with draft Productivity Commission reports today.

Mr Morrison has effectively buried the PCs report on financial services competition and reports in todays Adelaide Advertiser suggest Federal South Australian Liberal MPs are being let off the leash to attack his championing of the PCs model to reform the GST distribution.