Cyril Smith Photo: Rodhullandemu derivative work: Ukexpat, CC BY 3.0 via Wikimedia Commons Sir Cyril Smith, who has died aged 82, was the Liberal and then the Liberal Democrat MP for Rochdale from 1972 to 1992, and a much more complex individual than his bluff, no-nonsense northerner image would suggest. His size ensured that he was instantly recognisable, and his forthright views, expressed in a broad Rochdale accent, gave him considerable media coverage, particularly when criticising his own party.

He rarely withheld comments on individuals, whether friend or foe, but was hurt by criticism of himself, including being curiously sensitive to allusions to his girth. He changed party three times without ever changing his views, and made overtures to the then prime minister, James Callaghan, in 1977 urging the formation of a centre party.

He was dismissive of social status as a route to influence but a supporter of the royal family. He portrayed himself as an individualistic local MP, deeply critical of parliamentary flummery and opposed to the whip system, but accepted appointment as the then Liberal leader Jeremy Thorpe's chief whip in 1975.

Efforts by Private Eye to implicate Smith in scandalous activities with boys never stuck and appeared to have no effect on his electability. A committed member of the Unitarian Church, he nonetheless was the only Liberal MP to vote for the reintroduction of hanging.

Along with a sister and a brother, all children of Eva Smith, Cyril never knew his father, and the family struggled to survive in a one-up one-down Rochdale terraced house, cooking meals on the open fire, trekking 300 yards to the toilet, and, occasionally, burning the furniture to keep warm. The house next door fell down in 1945, so the family moved to a slightly larger one, which became his lifelong home.

After Rochdale grammar school for boys, he went to work in a tax office. A colleague got him involved in the Liberals' 1945 general election campaign, and a speech he made at an open-air meeting cost him his job. At the Liberal party assembly in 1948 he spoke out against conscription and, having made an impression, became Stockport's full-time Liberal agent. His candidate, having narrowly saved his deposit at the 1950 general election, advised Smith to join the Labour party.

In 1952 he became Rochdale's youngest councillor and Labour's first winner in the Falinge ward, which included the house his family had abandoned. Under Labour, Independent and Liberal banners, he never lost an election in that ward, which he represented until 1975 when he resigned, saying he had not been "pulling his weight".

Smith achieved a childhood aim in 1966 when he became Rochdale's mayor. Fiercely loyal to his mother until her death in 1994, he enjoyed the paradox of her being his mayoress while she was still the town hall charwoman.

However, after a dispute with his Labour colleagues over council house rents, he resigned from the party, forming an independent group with four other ex-Labour councillors. When Labour took control of the council four years later, they removed Smith from every position of authority, including 29 school governors' boards.

Smith rejoined the Liberals in 1968 and, though far from the unanimous choice, became the party's 1970 general election candidate. He suggested later that the local party's parliamentary election record had been "abysmal for many years", although the party had taken reasonable second places, in one instance with Ludovic Kennedy as its candidate. However Smith added 5,000 votes, again coming second.

In 1972 the sitting Labour MP, Jack McCann, died and it was obvious that Smith was the only feasible Liberal byelection candidate. An army of party workers arrived. Some, such as myself and Tony [now Lord] Greaves, met slightly shamefacedly in the streets of Rochdale, campaigning for a candidate regarded as uncomfortably to their right, "why are we here?" I asked Tony. "Because we've got key local elections next May," he replied. Smith romped home with an 11% swing and immediately, national Liberal poll ratings almost doubled. He was to hold the seat relatively comfortably at five subsequent general elections. As chairman of Smith Springs (1963-87), employing some 70 people, Smith was attacked from the left for being a capitalist while preaching industrial participation, but, as his autobiography, Big Cyril (1977), made clear, his management style was consistent with his politics. He noted that the company's works council voted unanimously against joining the Transport and General Workers Union.

He found himself embroiled in further controversy through his association with Turner and Newall, a Rochdale-based company involved in the manufacture and marketing of asbestos. Smith was its consistent advocate in parliament, even after a clear link between asbestos and the cancer mesothelioma was established. A year after speaking in support of the firm in 1981, he declared the ownership of 1,300 its shares.

Smith was a difficult colleague. His tendency to shoot first and to qualify later was exasperating, although he never seemed bothered to have embarrassing statements quoted back later. Addicted to self-publicity, he knew that criticising his own party guaranteed coverage. Another technique was to threaten - but not follow through - resignation from any current position if a particular course of action was taken. Notoriously dismissive of what he saw as stifling parliamentary rules, he frequently opted out of participation in the Commons for weeks on end.

He tended towards authoritarian views on all issues except education, and his friendship with James Anderton, the sometime Manchester chief constable who espoused controversial "traditional" values, influenced his law and order pronouncements.

In the mid-70s Smith was chief whip during the final months of Thorpe's leadership of the party, which came to an end over a blackmail plot arising from allegations of a homosexual affair with a former model, Norman Scott. Smith's admiration for Thorpe collapsed when he discovered that vital information had been kept from him. His disillusion was compounded when he was virtually sacked by Thorpe in a bizarre, late-night call to his hospital ward, where he was recuperating from illness. Smith formally resigned two weeks later.

At the leadership election that followed Thorpe's resignation in 1976, he strongly supported John Pardoe against the eventual winner, David Steel. Typically, he announced that he would not be campaigning in any constituency that voted for Steel.

Smith was at first opposed to the alliance with the Social Democratic party, stating in June 1980 that the Liberals were being taken for mugs and that any fourth party should be "strangled at birth". But by September 1981 he was openly supporting the alliance. By 1983 he was calling for the appointment of a deputy leader, stating that "the Liberal party has reached the stage where to disagree with David Steel is disloyalty, and where one man is able to dictate ... on the basis of personal loyalty exactly what the party must do". In March 1985, however, Smith was again talking about the Liberal party's "big blunder" in not stopping the SDP.

In 1992 he retired from parliament. He did not go to the House of Lords - whether a peerage was offered and refused, or simply not offered, is unclear - but he received a knighthood in 1988.

Smith's personal style was described by the political journalist Andrew Roth as that of an "undisciplinable but formidable Poujadist". For Susan Crosland, wife of the former Labour minister Tony Crosland, he was "the prototype community politician, the populist". This prevented him from using his undoubted intelligence and his communication skills to achieve far more. His success in transcending the disadvantages of his birth without acquiring any airs and graces, and without in any way abandoning his roots, seemed nevertheless to leave him with a curious inferiority complex. Perhaps his most revealing comment was made in 1985: "I don't believe that I have ever been acceptable to the Liberal party establishment. I was handy to trot out to attack the Labour vote because I was working class."

He is survived by his brother Norman. His sister, Eunice, predeceased him.

Sir Cyril Smith, politician, born 28 June 1928; died 3 September 2010

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