Q&A: Dispute over the intellectual case for full fiscal autonomy

A The SNP is backing full fiscal autonomy, where all taxes collected in Scotland are spent in Scotland. The unionist parties are backing the devolution of some income tax powers and a few others such as Stamp Duty.

Q What's this row about?

A Two economists, Andrew Hughes Hallett of St Andrews University and Drew Scott of Edinburgh, published Scotland: A New Fiscal Settlement last year, providing "the intellectual case for fiscal autonomy". They estimated that a 1 per cent increase in fiscal devolution could boost GDP by 1.3 per cent after five years.

Q Why the fuss now?

A Alex Salmond is using the paper to base his case for financial independence. But critics, including economist colleagues, say it's impossible to say what impact fiscal devolution would have. Profs Hughes Hallett and Scott stand by their work, however, saying it is based on international cases where tax and spending has been devolved.