The jargon: Where the powers of the land lie

SECTION 30 CHANGES: Orders that modify the rules governing the Scottish Parliament, to either remove or add to powers reserved to Westminster. UK ministers suggest their power of referendums should be removed and given to Holyrood, via a “Section 30”.

THE SCOTLAND ACT: The 1998 piece of legislation, passed by the previous Labour government, which created the Scottish Parliament and set out the powers it currently has.

SCOTLAND BILL: The new piece of legislation, tabled by the current coalition government, which will hand more powers over taxation to MSPs in Edinburgh. One option considered by UK ministers is to amend the bill so it also transfers powers over the referendum.

THE SUPREME COURT: The highest court in the UK. Under the Scotland Act, it hears cases on “devolution matters” and, therefore, could be asked to determine whether a Holyrood-run referendum is legal.

ELECTORAL COMMISSION: An independent body set up by the UK parliament to register all political parties, monitor spending by parties and ensure good standards are set in running elections.