The use and abuse of economic modelling has become so bad in Australia that we need to adopt a code of conduct for economic consultants, similar to those followed by auditors and actuaries, the Australia Institute says.

The Australia Institute is calling for a code of conduct to be introduced in the wake of the saga surrounding modelling produced by BIS Shrapnel on Thursday, which purports to show the economic consequences of restricting negative gearing to new residential properties.

The modelling was being championed by Treasurer Scott Morrison, who said it showed Labor's proposal on negative gearing was ill-designed.

It predicted that abolishing negative gearing on established dwellings would wipe $19 billion from Australia's gross domestic product and push up rental prices by 10 per cent.