David Windlesham, who has died aged 78, was a quiet man in public affairs, a liberal Tory who specialised in Home Office issues and, briefly, leader of the House of Lords during Edward Heath's administration. He was also a highly successful television executive.
A master of tact and conciliation, Windlesham found himself in an uncharacteristically controversial position when, in 1988, Thames TV broadcast an edition of its current affairs programme This Week which questioned how three members of the IRA had been killed by the SAS in Gibraltar. It provoked a storm of indignation, not least from the Ministry of Defence and the Foreign Office.
Thames invited Windlesham and Richard Rampton QC to conduct an independent inquiry. The Windlesham/Rampton report on Death on the Rock (1989) found several lapses in the programme, but stated that overall, "we accept that those who made [the programme] were acting in good faith and without ulterior motives". The report had taken three months to produce, contained 145 pages and was published.
But there was then a further storm: a rebuttal of the report was issued jointly by Downing Street, the Foreign Office and the Ministry of Defence. Windlesham stood his ground, renounced the fee that he would have received for his report and won the support of the Independent Broadcasting Authority. The episode underlined his dedication to media freedom and an ability to face down the Whitehall establishment.
The Windleshams belonged to the Hennessy family, parts of which had prospered through the distilling of cognac. They had Irish Catholic roots, and David was educated at Ampleforth college, North Yorkshire. He was commissioned in the Grenadier Guards for national service and stationed at Tripoli. He gained a law degree from Trinity College, Oxford, in 1957.
His political interests began with membership of the Bow Group. Founded in 1951, it provided a home for ambitious Conservative graduates, publishing on topics that would influence the party hierarchy. The leadership included Geoffrey Howe and James Lemkin, a liberal advocate of colonial independence. Windlesham was identified with Home Office issues and PR. He was twice chairman of the group (1959-60 and 1962-63), and was elected to Westminster city council (1958-62).
From university, he had gone to work for Associated-Rediffusion, and was involved with This Week in its early years. But in 1962, his father, the 2nd Baron Windlesham, died in a helicopter accident. At that time, David was a Conservative parliamentary candidate for Tottenham, north London, a forlorn hope, but on the path to membership of the House of Commons, where he would have joined Bow Group colleagues such as Howe and Patrick Jenkin. Instead, he went to the Lords, where his political horizon was inevitably limited.
His arrival coincided with Tony Benn's determination to remain in the Commons following the death of his father, Viscount Stansgate. Windlesham used his maiden speech to favour modest Lords reform, and paid a handsome tribute to Benn, whom he knew. During the six years of Conservative opposition from 1964, he played a modest role in the Lords, and his sympathies were clearly with Heath, whom he much admired. After the unexpected Tory victory in 1970, he became minister of state at the Home Office (1970-72), under Reginald Maudling.
His departmental work was onerous, but he fulfilled Heath's confidence, particularly with the immigration bill. Windlesham had a mishap with the patriality provisions, but otherwise mastered his brief. He also helped handle the industrial relations bill. A commentator noted that he "dealt with business with calm efficiency and considerable charm". Tall and slim, he spoke courteously and with precision.
His qualities of moderation were tested when he became minister of state at the Northern Ireland Office under William Whitelaw (1972-73). He was the statutory ministerial Catholic, but his religion made little impact, and he had departed before the ill-fated Sunningdale conference. In June 1973, he was appointed lord privy seal and leader of the House of Lords – at 41, the youngest since Lord Grenville in 1790 – and thus a member of the cabinet. The vacancy had arisen from the unexpected resignation of Lord Jellicoe in the wake of the departure from government of Lord Lambton in a minor sex scandal. Windlesham's term of office was dominated by the miners' strike that led to Conservative defeat in the February 1974 general election.
He continued as leader of the opposition in the Lords until the second, October, election of 1974. However, after that defeat he resigned the post and turned to business.
Windlesham's early TV career had led to a seat on the board of Rediffusion, where he was chief programme executive. He thoroughly enjoyed being managing director of Grampian (1967-70) and returned to TV in 1974, becoming joint managing director of the ATV network, and continuing as managing director (1975-81). He led his managers effectively, balancing the quest for quality with an eye on ratings.
As chairman of the Parole Board (1982-88), Windlesham maintained his liberal reputation, although he declined to parole Myra Hindley. His publications included four volumes of Responses to Crime (1983-2001).
As principal of Brasenose College, Oxford (1989-2002), he likened his quiet but authoritative handling of college business to "herding cats". He was a director of the Observer (1981-89); chairman of the trustees of the British Museum (1986-96); and a visiting professor at Princeton University, New Jersey (1997 and 2002-03). He also gave much time to Victim Support, serving as its president (1992-2001) and playing a key role in getting police support for its work, which was extended to crown courts. After most hereditary peers left the Lords in 1999, he was made a life peer with the title Baron Hennessy.
In 1965 Windlesham married Prudence Glynn. She died in 1986, and he is survived by their son and daughter.
David James George Hennessy, 3rd Baron Windlesham, politician and television executive, born 28 January 1932; died 21 December 2010