With Tony Blair formally passing the torch – some would say poisoned chalice – to Gordon Brown today, the reality of a Brown Premiership is looming ever larger. Brown’s challenge is to retain continuity whilst paradoxically making a break with the past. Fundamental constitutional reform is one of the few ways in which he can square this circle.

Gordon Brown launched his bid for leadership of the Labour Party today by pledging to “build a shared national consensus for a programme of constitutional reform that strengthens the accountability of all who hold power; that is clear about the rights and responsibilities of being a citizen in Britain today; that defends the union and is vigilant about ensuring that the hard won liberties of the individual, for which Britain has for centuries been renowned round the world, are at all times upheld without relenting in our attack on terrorism.”

Very little of that will come across as particularly surprising to veteran Gordon Brown twitchers. Brown has been making the link between identity and the need for constitutional reform for quite some time now, and in numerous speeches has indicated support for, among other things, House of Lords reform and making the power to wage war subject to Parliamentary approval. Behind the scenes however, something new does appear to be taking shape. At a Smith Institute seminar on Wednesday, Brown’s campaign manager and the Leader of the House of Commons Jack Straw stated that he had come to believe that the UK ‘needed’ a written constitution. Although this was a comment to a question and not a part of his speech, there is no question that he would have made such a statement without the tacit approval of his candidate. Nor is it the first time that a Brownite has made such a suggestion: last year Michael Wills MP wrote an IPPR pamphlet calling for the establishment of a constitutional convention. It is clear that this idea is being seriously considered by Gordon Brown and his team. In a country where the political establishment is so enraptured by ‘flexibility’ (read: arbitrariness) of its uncodified constitution, for the person so close to the top job to be even considering such a project is unprecedented.

All of this is to be warmly welcomed. The entrenchment of a UK constitution has always been the key overarching aim of Charter 88 since it was formed nearly two decades ago. Three questions however remain.

First of all, is this to be merely the codification of existing conventions and the entrenchment of existing ‘constitutional’ legislation such as Human Rights Act, or is Brown advocating a more wide-ranging review? To an extent this is a bit of a trick question as any codification will involve establishing principles in law that are likely to be controversial and

Secondly, who will have control of the process? The standard UK approach to such things is to appoint a high court judge, retired senior civil servant or elder statesman to chair a Royal Commission filled with the great and the good. Such an approach is unlikely to capture the public imagination. Michael Wills suggested holding a special election to form a one-off constitutional convention. The Citizens Assembly model being pioneered in Canada, where a random group of citizens are selected to deliberate on constitutional issues, is worth considering.

Fundamentally, the mistake of drafting the Human Rights Act largely behind closed doors must not be repeated: if the public are to identify with this document, feel that it articulates British values and have a sense of ownership of it, they must feel they have been given a real say over its content. Even a referendum on the final document, while necessary, will not by itself be sufficient.

Thirdly, where does this leave the existing programme of democratic renewal? Newspaper reports suggest that Gordon Brown plans to shelve House of Lords reform until after the General Election. Notwithstanding the difficulty of getting this reform through both Houses of Parliament before an election must take place, he would be wrong not to try. If, after the historic vote in the Commons for reform earlier this year, all we have to show for it is a necessarily vague line a manifesto, we will be back (almost) to square one. If however, the programme continues and the new Prime Minister can at least steer a specific Bill through the House of Commons, then the process will become hard to stop. It will also signal a commitment to reform in a way that no manifesto commitment ever could, and help inform the work of any future constitutional convention.

An important litmus test will be how he deals with party funding reform. Sir Hayden Phillips’ final report on party funding is likely to be landing on the new Prime Minister’s desk almost as soon as he takes office. If he chooses to shelve it or to cherry pick from it he will risk sending out the worst possible signal at a time when he can least afford to.

From both his own self-interest and the good of the country, there is every reason why Gordon Brown should want to embrace the constitutional reform agenda. That he has clearly grasped this fact is a very welcome sign of things to come, but very shortly he will need to focus his attention on specifics. If he can remain committed, he will leave a golden legacy, but it will mean taking on an establishment that will not surrender power lightly.