John Swinney faces questions at the Finance Committee this morning over the potential clash of interests involved in members of the Government's Council of Economic Advisers also being appointed to the new commission.
Opposition MSPs have questioned how advisers such as Lady Susan Rice and Professor Andrew Hughes-Hallett can act as watchdogs on tax and spending projections, but Mr Swinney, in a written submission ahead of today's appearance, dismisses this criticism, insisting: "The roles of the Commission and the CEA are not in conflict.
"The Commission will be responsible for scrutinising forecasts of tax revenue prepared by the Scottish Government, and reporting the outcome of that scrutiny to the Scottish Parliament and to the public."
Mr Swinney is offering to make SFC members subject to the same code of conduct applied to members of other devolved bodies.
He said: "I fully agree with the committee that, the independence of the individual members from Government or perceived conflict of interest must be demonstrated and safeguarded."