MR Tony Blair has done no more than state the accurate constitutional position of a devolved Scottish parliament within the United Kingdom.

As is stated in the recent publication Devolution to Scotland, the Westminster Parliament will remain the sovereign legislature of the United Kingdom after a Scottish parliament is established - the granter and guarantor of the powers of that parliament.

Despite the predictable brouhaha whipped up by the opponents of devolution, this fact will not prevent a Scottish parliament from legislating in respect of any of the powers devolved by Westminster, nor prevent it from deciding spending priorities within the overall Scottish assigned budget.

This approach is wholly consistent with the Claim of Right adopted by the Scottish Constitutional Convention in 1989 by which the Convention declared it was the sovereign right of the Scottish people to determine the form of government best suited to their needs.

A two-question referendum on the devolution package espoused by the Convention partners is therefore the most appropriate modern-day embodiment of that popular sovereignty, while acknowledging that the United Kingdom Parliament will remain the supreme domestic law-making authority within the United Kingdom.

The United Kingdom Parliament would only cease to be sovereign in the domestic sphere if its powers were limited by some higher form of law such as a written constitution.

In Devolution to Scotland the idea is proposed that when a devolved Scottish parliament is established following a pre-legislative referendum in Scotland, there should be no change in its constitutional status without a further referendum. A provision to this effect could even be inserted in the legislation creating a Scottish parliament. Even so, it represents a practical rather than a cast-iron legal brake on the powers of the United Kingdom Parliament.

The pre-legislative referendum is an essential element in providing a Scottish parliament with democratic legitimacy and longevity. All political parties must declare how they will campaign in that referendum if the Scottish people are to make an informed choice on May 1. To fail to do so is to treat the Scottish electorate with contempt.

William Bain,

The Law School,

University of Strathclyde, Glasgow.

April 4.