Today the new Attorney-General has to perform what amounts to open heart surgery — on herself. Just one month into office, Baroness Scotland of Asthal will publish proposals for the reform (read dismantling) of her 500-year-old office. The move has been foreshadowed by Gordon Brown when he published his governance reforms earlier this month, so it comes as no surprise: Baroness Scotland will have taken up the job knowing that her first task was to take the scalpel to it.

The role of the Attorney-General has been an obvious anomaly for some time. When Tony Blair decided to break up another ancient office — that of Lord Chancellor — it was on the basis that there was an inherent conflict in the jobs of being a judge and head of the judiciary, a Government minister and Speaker in the House of Lords. It was time, many critics said, for a clearer separation of powers.

And so the former Prime Minister sacked his then Lord Chancellor and launched constitutional reform. He failed to get rid of the office of Lord Chancellor but the Lord Chief Justice is now head of the judiciary and the Lord Chancellor — also now the Justice Secretary — is not a judge or Speaker. And the law lords, the highest court in the land, are being removed from the House of Lords and turned into a Supreme Court.

At that time, no one took much notice of the similar tensions in the role of the Attorney-General, who likewise wore several apparently conflicting hats. But under the tenure of Lady Scotland’s predecessor, the clamour for reform began to mount. Earlier this month it culminated in a hard-hitting report from the Constitutional Affairs Committee of MPs.

Under the chairmanship of Alan Beith, MP, the committee concluded that the “status quo” was not an option. The ancient office was tainted by allegations of political bias and should be broken up and reformed, it said.

Public confidence in the role of the Attorney-General, the Government’s chief law officer, has been “significantly affected” by a series of recent controversies, the MPs added: the legal advice given by Lord Goldsmith, QC, on the war in Iraq, the halting of the Serious Fraud Office investigation into the BAe Systems arms deal with Saudi Arabia and Lord Goldsmith’s insistence in a role on any “cash-for-honours” prosecution.

They also found confusion about the overlap in the Attorney-General’s roles. These include overseeing the prosecution services, advising the Government on legal matters as its chief legal adviser and sitting in Government as a minister who, in the case of Lord Goldsmith, “repeatedly” attends Cabinet. The office-holder is also guardian of the public interest, with a duty to “uphold the rule of law” — a role in which he brings, for example, prosecutions for contempt of court.

The heart of the problem, as Mr Beith put it, is the “need for real and perceived independence in giving legal advice to government, and making decisions about important and sensitive prosecutions that may involve government, while sitting in that same government as a Cabinet-level office-holder, appointed by the Prime Minister and taking the party whip”.

The role should be reformed, the report said, so that “Parliament and the public can be clear about the basis on which decisions are taken”. The MPs called for an end to the Attorney-General sitting in Cabinet and to being the legal adviser to ministers. That job should be handled by a career lawyer, the MPs say, not a political appointee or politician or member of the Government. They also recommend that he no longer supervises the Crown Prosecution Service and other prosecuting authorities — a superintendence that had emerged as one of the most “problematic” aspects of the office. Instead, that role should go to a minister within the Ministry of Justice who would carry out the ministerial functions conducted by the Attorney-General: namely being one of the three justice ministers responsible for the criminal justice system. And where that minister instructs the Director of Public Prosecutions or other head of a prosecuting authority on matters of public interest, the Justice Secretary would be accountable to Parliament for that instruction, they say.

Lord Goldsmith had argued the case for a lawyer at the heart of government. But the MPs wryly noted: “The inept handling of the beginning of the process of reform that culminated in the Constitutional Reform Act 2005, and the secretive process of establishing a Ministry of Justice, which was trailed in the newspapers before consultation either of the judiciary or the Lord Chancellor, were seemingly unaffected by the presence of lawyers within Cabinet.”

Gordon Brown has made it clear that in future the Attorney-General should not be involved in key prosecution decisions unless required by law or national security considerations. Further reforms are likely to draw heavily on the MPs’ report.

On his last day in the post, Lord Goldsmith insisted that he was a lawyer first and foremost and always put political considerations aside in carrying out his role. But critics, including Mr Brown’s new constitutional adviser, Lord Lester of Herne Hill, have pointed out that the issue is one of perception. It is hard to retain public confidence when there is an appearance of conflict of interest, whether imagined or real.

Lord Goldsmith retains a high reputation as an outstanding lawyer. But as a lawyer in increasingly political waters, he came adrift. Ironically, though, it was his own insistence on that political role — one of the most political assumed by any Attorney-General — that sealed his fate, and that of the office in its present shape.

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