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So it's all change in the top jobs of the judiciary. Sir Igor Judge will be the next Lord Chief Justice, taking over on October 1 when Lord Phillips of Worth Matravers becomes the new senior law lord.

The appointment comes as no surprise. There was no other contender and Sir Igor, currently head of Criminal Justice and deputy Lord Chief Justice, is widely supported. But is it just musical chairs, or will the change mark a shift in policy or style?

The job has never been more crucial. On top of the traditional duties of handing down leading rulings and influencing the stance of the Court of Appeal, the Lord Chief Justice these days is also head of the judiciary. That is not just being a figurehead.

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When the Lord Chancellor gave up the role of heading the judiciary under the Constitutional Reform Act 2005 and it went to the Lord Chief, it came along with the panoply of a mini-Whitehall style department. There is now a staff of more than 60 serving the senior judiciary and their new administrative responsibilities: deployment of judges, training, welfare and discipline.

But the job is more than being an administrator. With the Lord Chancellor no longer the official mouthpiece of judges in government, it is up to judges themselves to speak up when they need to be heard. And the Lord Chief Justice is the one to do it. Not on everything and not, generally, on social issues of the day that might come before the courts for adjudication. But on justice issues that will affect the way the courts operate or the prosecution system, he should speak up. The reason is that this is the only way, often, that the view of the judiciary will be heard. Leaks of e-mails or judicial responses are no substitute.

This can be dangerous or hostile territory for the uninitiated. And for judges it is also, often, territory into which they would rather not venture. But in this new dispensation, with the judicial arm of the constitution now more separate and more clearly independent, it is crucial that - every so often - they do venture into it.

Lord Woolf made regular public pronouncements, generally on penal policy and the importance of community sentences and reserving jail as a last resort. He also spoke out on sentencing issues - and got into hot water more than once because his remarks were either misinterpreted or, on occasion, not sufficiently unambiguous to appear without distortion in the press. He found himself unexpectedly in the headlines when he apparently called for all mobile phone robbers, however young, to be jailed.

But that is not a reason not to do it. Lord Phillips came in for criticism for failing to speak up for the troops when judges were under fire over alleged "soft" sentencing. Lord Phillips, as their leader, some felt, should have spoken out to put the record straight and explain that such sentences were reached in strict compliance with Government guidelines. The judges had little discretion.

In general, though, Lord Phillips was a little luckier than his predecessor, or perhaps more cautious in his public pronouncements. But even he got his fingers burnt. In his first important policy statement, he produced a carefully thought out set of sentencing guidelines - to find them seized upon in the tabloid press, which derided him as a "softy" whose proposals would lead to a rise in mugging.

So what will Sir Igor do? By nature more of a traditionalist and cautious, he is popular with the judiciary, particularly the criminal rank and file, from whence he hails. They feel he will understand their concerns in a way that perhaps his last three predecessors, all from non-criminal law backgrounds, did not.

But his style is not that of the last criminal Lord Chief Justice, Lord Taylor of Gosforth, who was happy not just to lead from the front but to be seen and heard to do so. Rather, on contentious issues, he will prefer behind-the-scenes politics to megaphone diplomacy.

He takes seriously the boundaries that divide the judiciary from the executive, regularly reiterates that judges must apply the law and that this is their role, and insists it is not for judges to comment on matters of party political dispute nor social issues. Not for him, probably, a speech on such a sensitive topic as Sharia, as given by Lord Phillips last week.

To some extent he will not be under such pressure when judges are misunderstood. A team of five judicial spokesmen is being trained to put out the view of the judges in the media when the next furore occurs, although Sir Igor would be expected to speak up on the big issues.

Yet it would be retrograde if Sir Igor was ever tempted to retreat to the days of Lord Lane, who felt that judges should be seen and heard only in court, never outside it. Even he, though, was moved to speak out to oppose government proposals to scrap trial by jury.

Things have moved on. The job demands that the Chief gives voice to judicial views when appropriate and not just on trades union issues of pay or pensions, staffing or buildings. Of course judges cannot formally or even informally sit around the table with ministers and discuss whether, for instance, a specific proposal would be ruled by them to be in breach of the Human Rights Act - as Charles Clarke, the former Home Secretary, wanted. Apart from anything else, they could then find themselves judging the new law in a case in their courts. But they can highlight the dangers of particular proposals before they reach the statute book - and be upfront about it. Their views will emerge anyway.

Sir Igor is media-friendly, persuasive and thoughtful. He may not like the public aspect of his new role as much as some have done. But the job demands it - and he is well up to the task. Better to flag up the pitfalls of an impending piece of legislation than spend years lamenting the problems it causes the courts.

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