Lord Lyell of Markyate: Lawyer and MP who endured a turbulent time as Attorney General in John Major's Conservative government

During the long years of Margaret Thatcher's dominance of Conservative and national politics, Nicholas Lyell occupied a somewhat anomalous position on the political spectrum and never gained the advancement which, his friends believed, his talents merited. He served for seven years from 1979 as Parliamentary Private Secretary to Sir Michael (later Lord) Havers, who became Attorney General in the 1979 government. It was a long time for an able young man to serve in the ranks of those commonly described as "the lowest form of parliamentary life". He subsequently held junior office at the then Department of Health and Social Security before becoming Solicitor General in 1987 and – his final appointment – Attorney General in 1992. After the Conservative general election defeat of 1997, he accepted William Hague's invitation to serve as Shadow Attorney General.

Nicholas Walter Lyell was born on 6 December 1938 into a legal family, his father, Sir Maurice, being a High Court judge. He was educated at Stowe and Christ Church, Oxford, where he took a good degree in history. He had long been of a mind to follow his father in the profession of law, but along the way he worked at his stepmother's family firm of shipbuilders, Walter Runciman. He was called to the Bar in 1965 and decided to specialise in commercial and industrial law.

Lyell was, almost certainly, the last political figure to be, at one and the same time, a fully active lawyer and a fully active politician. Unlike predecessors of his such as Quintin Hailsham, Geoffrey Howe and Patrick Mayhew, all of whom had been Law Officers of the Crown, he never went on to enjoy formal Cabinet office. And this, many of his Conservative friends concluded, was a great pity, for the precision of his legal mind would have been of great advantage to Conservative governments in the closing years of the 1990s had he held Cabinet office.

However, there was always a struggle in his mind about whether he was a politician or a barrister. He liked (as one of his friends recounted to me) to boast – and he was not a man given to boasting – that he was the longest-serving Law Officer of the 20th century. His record gave him a joy which was not available to him either in his legal or his political career.

Though precise and assiduous in his work, Lyell was not, perhaps, the most brilliant of lawyers but, then, he served in a set of Chambers headed by Lord Alexander of Weedon, one of the most outstanding barristers of his time; and his colleagues were, generally, exceptional practitioners. In Parliament, however, he enjoyed a relatively tranquil time as a Law Officer – though he did contribute to Margaret Thatcher's revolutionary reforms of trade union law – until the arrival of John Major as Prime Minister in 1990. Thereafter, complicated and controversial problems fell, one after another, on his hapless head, as the Major government, despite an unexpected general election victory in 1992, fell headlong to destruction in the general election of 1997.

It should be understood that a Law Officer, though a politician and a member of a government, owes his principal duty to the law itself and, from time to time, the line between politician and lawyer is a difficult one to draw. His primary political duty is to advise his colleagues on whether or not any course of action upon which they propose to embark is, in the current state of the law, legal or illegal, or whether the law needs to be changed to advance a given policy.

He may also be called upon to give advice to a colleague on whether a particular legal action is justifiable in law, or wise in politics. Every difficulty Lyell faced between 1990 and 1997 found him struggling between these two demands on his time and judgement. These difficulties, moreover, began as trivial, and moved on to the portentous.

Shortly after Major became Prime Minister an underground magazine, Scallywag, published an allegation that the Prime Minister had had an affair with Clare Latimer, a caterer who from time to time cooked for functions at 10 Downing Street. These allegations were repeated, at great length, in the New Statesman. Major wanted to know whether it would be advisable for him to sue. Lyell advised him that he had an overpowering legal case but that politically it would be advisable not to. Eventually, the magazine settled out of court.

The next serious case in which Lyell was involved concerned the case of the Turkish Cypriot businessman Asil Nadir, who eventually fled the country to avoid prosecution for fraud and criminal deception. It had elements of the comical and bizarre about it, but it also had very serious and dangerous political implications.

The Minister of State at the Northern Ireland Office, Michael Mates, was a friend of Nadir. On one occasion Nadir had lent him a car. When trouble loomed over the businessman, Mates gave him a present of a watch, on the back of which he had had inscribed a message, "Don't let the bastards get you down". Mates wrote to Lyell suggesting that he might intervene in the legal process on Nadir's part; Lyell informed the Prime Minister and, after a somewhat protracted time of controversy, Mates was required to resign his office.

Next came the controversy over BSE and the decision of Britain's partners in the European Union to ban the import of British beef. One of the options favoured by a majority of the Cabinet was to respond by banning at least some continental imports to Britain. Lyell had the painful duty of informing his party colleagues that such a reactive ban would be illegal, advice which gained him no political friends. This situation was not dissimilar to that faced by Sir Peter (later Lord) Rawlinson in 1970, when he was obliged to advise the Heath government that they could not prosecute the Palestinian terrorist, Leila Khaled, because her attempt to hijack a British aircraft took place outside British airspace.

Worse was to come. Before the Gulf War a British firm, Matrix Churchill, sold arms to Iraq. They did this, as is now apparent, with the verbal connivance of the Foreign Office, representatives of which suggested that the military material should be labelled "mining machinery". The business duly came to light, and ministers were accused of bad faith. The directors of Matrix Churchill were prosecuted for the illegal export of arms. But during their trial, a government minister, Alan Clark, confessed to the court that he, and others, had been less than truthful in their accounts of dealings with Iraq. The case collapsed, but Matrix Churchill was destroyed and two of its directors made bankrupt.

The reverberations of this affair were exceptionally noisy. To still discontent John Major decided to set up a committee of inquiry under Lord Justice Richard Scott. The committee began its work in 1993, and reported in 1997. Scott's conclusions were – if partial – devastating. He had come to the view, particularly, that Clark, William Waldegrave (another relevant minister) and Lyell had deliberately misled the original court, the inquiry and – most important – the House of Commons on the whole matter of Britain's commercial relations with Iraq. The Prime Minister himself did not escape censure.

Lyell immediately proffered his resignation. It was refused. Major, throughout his years in office, tried in every way to prevent, or at least delay, ministerial resignations: he was trying to hold a fractious party, and a fractious government, together, and he could not, he thought, afford too many such departures. The Matrix Churchill affair, none the less, was the effective end of Nicholas Lyell's political career. He was created a life peer in 2005.

The last years of Lyell's life were made painful by an operation for cancer, and by the subsequent chemotherapy he had to undergo. However, he met his last challenges as he had met every difficulty in his life, with fortitude and stoicism. It is as a decent and brave man that he will be remembered.

Patrick Cosgrave

Nicholas Walter Lyell, politician: born 6 December 1938; Solicitor General 1987-92; MP (C): Hemel Hempstead 1979–83, Mid Bedfordshire 1983–97, NE Bedfordshire 1997–2001; Attorney General 1992-97; Kt 1987; cr. 2005 Life Peer, of Markyate; married 1967 Susanna Fletcher (two sons, two daughters); died 30 August 2010.

Patrick Cosgrave died in 2001. This obituary has been updated.