So what do law officers do anyway?

THE POLITICAL strike by Michael Heseltine against his Cabinet rivals has put the spotlight on one of the most opaque areas of government: its law officers.

As Labour's front bench this weekend redirected its fire away from Sir Nicholas Lyell, the beleaguered Attorney General, in the hope of taking bigger ministerial scalps, the true cost of getting in a muddle with the law began to emerge.

A new official report shows that the Government spends more than pounds 2bn a year to sustain the Lord Chancellor's department, and the cost is rising by about 10 per cent a year. The vast bulk of this goes on legal aid, but the bill to keep ministers on the right side of the law is also substantial.

Lord Mackay of Clashfern, the Lord Chancellor, on pounds 120,179 a year, presides over a legal establishment employing 2,489 civil servants in organisations ranging from the much- criticised Crown Prosecution Service to the Public Record Office. Yet though his office stretches back more than 600 years, and he ranks second in the Cabinet after the Prime Minister, he does not give legal advice to ministers.

That is the task of Sir Nicholas, MP for the ultra-safe Tory seat of Mid Bedfordshire. He was made Solicitor General in 1987, and was appointed top law officer by John Major after the last election.

His function dates back to the 13th century. In medieval times the role was that of the King's Attorney, responsible for maintaining the sovereign's interests before the courts. Until 1893, the office-holder was a practising barrister conducting the Government's business from his chambers. Today, he has a staff of at least 10 lawyers and double that number of support staff.

Sir Nicholas advises the Cabinet, but he is not a member of it. He is the Government's chief legal adviser, answering questions in the Commons, and is politically responsible for the Crown Prosecution Service. He is also the leader of the English Bar and presides at its general meetings. His consent is required for bringing high-profile criminal prosecutions, principally those relating to offences against the state and public order and corruption.

Very occasionally he will lead a prosecution, but he cannot engage in private practice. For all this he is paid pounds 43,456 on top of a reduced MP's salary of just under pounds 24,000.

Every Attorney General manages to have the worst of both worlds. He must be a practising lawyer and an MP. Other lawyers complain that he is too much of a politician. Other politicians complain that he is too much of a lawyer.

To help cope with this crisis of identity, he has a deputy, the Solicitor General, another political appointee. In this parliament Sir Derek Spencer, MP for Brighton Pavilion, a former Crown Court recorder, holds the job.

The law officers are very fussy about proclaiming their independence of government when they undertake prosecutions. Lord Mackay said in his Hamlyn Lecture last November: 'When the Attorney is acting in this capacity, he is doing so on his personal responsibility and is not answerable to the Cabinet or subject to any direction of any sort from a ministerial colleague.

'It may be for him, if he judges right, to take account of any considerations that a colleague may put before him, but the decision is for him ministerially, and for him alone.'

Sir Nicholas may not have to listen to his Cabinet colleagues, but they have to listen to him. And the job is at least as political as it is legal. During the 1986 Westland affair, for example, Sir Michael Havers threatened to call the police in to Downing Street to discover who leaked a critical letter from his Solicitor General, Sir Patrick Mayhew, to Michael Heseltine.