Thinking the unthinkable is what constitutional lawyers are paid to do. Many are now saying that with the daily revelations about improper expenses claims from beleaguered MPs the Queen should step in and dissolve Parliament — against the Government’s wishes — forcing a general election to compel MPs to stand for immediate re-election after a scandal on the scale of that of the pre 1832 rotten boroughs. Trust has now been destroyed. It can, so the argument runs, be rebuilt only by a neutral third party, the Queen, and not by a self-interested and wholly discredited cabal of politicians.

Could the Queen really dissolve Parliament in that way or is it unthinkable? A few weeks ago, I represented the Government of Fiji before the Fijian Court of Appeal. The court rejected the argument that the President had emergency powers allowing him to dissolve Parliament outside the terms of the Constitution. Interestingly, the court drew a distinction between the Crown prerogative of the English Crown and the President of a republic who, the Court said, had only the specific and limited powers given to him by the written Constitution.

But the UK does not have a written constitution. Some maintain it should. In the absence of a written constitution the Queen still has the so-called personal prerogatives. One of them is the power to dissolve Parliament.

There is no “law” that prevents the Queen from dissolving Parliament. But there is an important constitutional convention that enables the Prime Minister alone to decide the timing of a dissolution and general election and to advise the Queen.

It has from time to time been suggested that the Queen has a personal discretion in the matter and that her discretion can, in fact, be exercised despite prime ministerial advice to the contrary.

There is limited support for this view. But it is very old. In November 1834, the Prime Minister Lord Melbourne had to appoint a new Commons leader and a new Chancellor (who by long custom, must be drawn from the Commons), but the only candidate that Melbourne felt suitable to replace Lord Althorp as Commons leader was Lord John Russell, who William IV (and many others) found unacceptable due to his Radical politics. William claimed that the ministry had been weakened beyond repair and used the removal of Lord Althorp as the reason for the dismissal of the entire ministry. With Lord Melbourne gone, William chose to entrust power to a Tory Sir Robert Peel.

However, since 1834 there has been no exercise of the personal prerogative in relation to dissolving Parliament. The prevailing view is, therefore, that a constitutional convention now prevents it. The question is whether or not the Queen could act in defiance of that convention. This, in turn, raises the issue — rarely addressed — of the effect of a constitutional convention.

Anyone speaking and writing about conventions is faced with a problem. Conventions are closely related to law but they are not themselves law. Courts have never had to decide the legal effect of a constitutional convention because conventions do not determine legal rights. Occasionally, courts such as the Canadian Supreme Court in the 1980s have been willing to define the scope of a particular convention (in that case which Canadian body should ask the UK to pass the necessary legislation to give effect to Canada’s break with the UK) but they have only ever done so extra-legally. A constitutional commission would have been able to do precisely the same thing.

The short answer to whether the Queen would ever do the unthinkable and dissolve Parliament contrary to the Government’s wishes is that there is, almost certainly, no legal impediment to her doing so. But the constitutional objections against such a course would be likely to prove overwhelming unless there were some constitutional crisis.

It is, though, ironic that at the start of Gordon Brown’s short honeymoon with the British public one of his first acts was to seek to whittle down the royal prerogatives almost to vanishing point. It was, like his handing over of interest rate variations to the Bank of England at the start of the Blair era, an initially popular move since lawyers of a republican bent have always distrusted the possibility of discretionary powers unregulated by Act of Parliament.

Yet that is the difficulty with the present crisis. The mounting public anger at the lack of transparent and accountable self-regulation by MPs cries out for the exercise of discretionary sovereign power. The last thing the public wants is a Parliament-driven solution to a problem created by the very MPs who constitute Parliament and many of whom have the strongest possible interest in a “solution” that will not serve the public interest.

Richard Gordon, QC, is a constitutional and administrative lawyer, a Visiting Professor at UCL and an Honorary Visiting Professor at the Chinese University of Hong Kong

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