The timing of Alan Howarth’s switch from Conservative to Labour benches came as a great shock to his erstwhile colleagues.

The profound nature of his disagreements with Government policy did not. For months now the MP for Stratford-on-Avon, a former education minister, has been ploughing a lonely furrow through singularly unpromising ground.

His one-man campaign for the liberalisation of social, educational and economic affairs reached a crescendo in July when, in the House of Commons, he laid into almost every field of current Government policy.

Grant-maintained and public schools came in for a hammering, as did cuts in the training budget. But this was only part of a thrust at the heart of his party’s thinking.

He called for consensus politics, for government-sponsored job creation, and for a level of sympathy towards the dispossessed, including beggars, that makes Labour’s Jack Straw look like a wild man of the Right. Following that the real surprise, it might be said, is that anyone was surprised at all.

This week, the 51-year-old stood accused of everything from disloyalty to questionable mental health, as Education and Employment Secretary Gillian Shephard appeared to suggest that the recent break-up of his marriage had left him in a “turbulent” state of mind. She should know better, replied Mr Howarth.

He entered Parliament as the MP for his safely Conservative seat in 1983. By then he had already been director of the Conservative Research Department and vice-chairman of the party itself, receiving a CBE for his troubles. It is, perhaps, these impeccable credentials which have in part prompted the outraged cries of treachery.

Once in Westminster, he enjoyed a smooth ride through the whips’ office to the position of Higher Education Minister, a post which in 1992 he suddenly, and to general surprise, resigned.

Mr Howarth’s early political stance was markedly right-wing. He was, for example, closely associated with the No Turning Back group of Conservative MPs who, in the early 1980s, insisted that the Government should forge ahead with Thatcherite policies.

How, it has been repeatedly asked, can this square with his new-found liberalism? He replies that his right-wing views were restricted to economics.

“It was very much a live argument in 1983. I believed very strongly that if we were to create wealth and generate resources, we did actually have to be disciplined about public finances - which is exactly the position that Gordon Brown has now adopted.

“I did not subscribe to the position of the No Turning Back group on social issues, on the welfare state and the extent to which we should seek radically to privatise a whole range of activity you could term as being part of public service.

“I refused to sign the original No Turning Back pamphlet but I did a great deal of work on the second pamphlet, Save Our Schools.”

This, he says, set out a blueprint for the local management of schools, a policy which eventually found its way into the 1988 Education Reform Act.

His strong dissatisfaction with party policy appears to date from his spell with the then Department for Education and Science where he found, to his dismay, that the Treasury had an endless appetite for draconian cost cuts in polytechnics and universities.

By 1992, he said, he had become very unhappy with the squeeze on resources in higher education. “We were right to go for the early phase of rapid expansion. It was appropriate because it was quite possible for the institutions of higher education to find economies.

“In my later period of office, however, it became very clear to me that we were going beyond the point at which our quest for economies could provide greater efficiency. In fact, through squeezing the unit of resource, the quality of studies was very much at risk.”

And as a consequence, he says, he decided to return to the backbenches. Since then his dissatisfaction has intensified. He has campaigned for those with disabilities and special educational needs. He was angered by the Government’s opposition to the anti-discrimination Bill. His own son, Charlie, has cerebral palsy, which, he says, has profoundly affected his outlook.

“For me it’s been a joy to be Charlie’s father. I’m always aware of his abilities, his enjoyment, and his great future potential. My experience has been fortunately a formative one.

“One of the reasons why I have become so deeply dissatisfied with the Conservative party is I take it as axiomatic that a decent society wishes to offer equal opportunities and all the help it can give to people who are disadvantaged.

“The Conservative party’s equivocation about legislating for civil rights across the board in every field of public life has shocked me. I failed with the party to try to persuade them to develop their views and adopt a broader, humanitarian approach. I have found their equivocation very disappointing, very regrettable.”

But he makes an honourable exception for Eric Forth, the Minister of State who until recently dealt with special educational needs.

Central to Mr Howarth’s criticisms of Conservative education policy are low levels of funding and, in particular, a preoccupation with the structure of the system, rather than its results. On both counts his view is shared by the Labour party and, curiously, by Gillian Shephard, as she explained in her leaked memo to John Major.

“I have been presented as always mad keen on opting out,” says Mr Howarth.“That was not part of the argument made by the No Turning Back group and it was not in the pamphlet. While I have enormous admiration for those opt-out schools that I have seen, and while it is very clear that there was a remarkable psychological release for them, I still have misgivings about the principle of fragmenting the education service.”

This concern, he says, is tied up with the place of Britain’s public school system - which he believes has been divisive.

“As the son of a public school teacher and head, as someone who attended a public school, and whose children attended public school, I have come to the conclusion that, whatever the excellence of these schools, we have failed to provide a fit system of education in the way that the French and Germans have done. It has been a very significant misfortune for this country.

“Successful middle-class parents have opted out of the mainstream of national education in a way that has been socially divisive. It is unfortunate that, politically, the kind of pressure these parents might have been bringing to bear on behalf of their children in the state system has not been there. ”