Equality is a principle that is constantly being tested to destruction. Harriet Harman’s proposed Equality Bill is a startling case in point. She is right to insist on equal pay for equal work; that is a principle that nearly every woman in the country must believe in passionately, and by now most men as well. It is clearly wrong to pay one person less than another for the same work, simply because of her sex (or indeed his colour or age). It is and ought to be illegal.

However, this principle soon grows into much more ambitious and more nebulous ideas about equality at work, including the dubious concept of equal representation – equality not just by person but by group. These ideas, as Harman’s bill clearly shows, lead not only towards an explosion of bureaucracy and cost, but also towards injustice and inequality – towards the destruction of the very principle.

Harman proposes to replace a “thicket of legislation” against various different kinds of discrimination with a single duty of equality covering everything from race and gender, through religion and belief to sexual preference and age. That seems reasonable, and it is true that despite the Equal Pay Act of 1970 there are still persistent, incontrovertible inequalities at work. There are some disgraceful cases both at the top and the bottom of the market. Women employees in local authorities are in some cases still being paid less than men for comparable semi-skilled jobs, and employment tribunals regularly expose huge gender differences in City high-flyers’ pay.

What’s more, the gender pay gap – these weighty subjects create horrible expressions – still appears to be marked in government itself. According to civil service number crunchers’ figures for 2006, it was 26% in the Treasury, 21% in the transport department, 17% in Defra, 16% in the culture department and 7% in the work and pensions department. (However, in the government equalities office, women were paid 4% more than men; do not smile.) Harman explained with passion on the Today programme that a part-time woman worker is paid 40% less than her full-time male equivalent. “Do we think she is 40% less intelligent, less committed, less hardworking, less qualified? It’s not the case. It’s entrenched discrimination.”

Her plan, or part of it, is to allow employers to discriminate in favour of women and ethnic minorities, against equally qualified white men. She has other inflammatory suggestions, such as forcing public sector employers (and “encouraging” private ones) to reveal what they pay people, and explain what they are doing to close the gender gap, and to provide opportunities for ethnic minorities and disabled people. One could argue about all that – I’m not sure I am entirely opposed to employers revealing what they pay their employees, though the unintended consequences would no doubt be awesome.

These issues, though important, are secondary. What really matters is that we have a minister who is prepared, with the full backing of a Labour government, to enshrine in law, in the name of equality, the principle of institutionalised inequality against men. Employers will be free (and, it seems, pressed, by other provisions of this bill) to take positive action to recruit more women and ethnic minorities, to achieve what they have learnt to assume would be a “better balance” within their companies.

White men are no longer to be equal to everyone else; they will lose their rights in employment tribunals (unless they are beyond retirement age, when they may possibly regain them); they are to pay for the sins of their fathers (or rather for the sins of their fathers’ bosses) against working women and against ethnic minorities by being unjustly treated in their turn. And Harman is prepared to do this terrible thing on the basis, merely, of unexamined assumptions about the facts.

For it is an unexamined assumption that equality must be connected with representation. Why do people so often assume equality for women – in, say, nuclear physics or welding or the police force – must mean the representation of women in equal numbers in those fields? If a certain percentage of policewomen are not Muslims or Hasidic Jews, does that of itself mean they have been discriminated against? Clearly not. And why do people assume that women earning less over a lifetime, and being underrepresented in senior posts, must of itself mean they were discriminated against?

Both assumptions are irrational. Women and men are different, and make different choices. We still understand little about such things, but are beginning to recognise that women often choose to work less, or less regularly, or with less responsibility than one would have predicted on their abilities alone. Many have other priorities.

We are also recognising that across a population women’s and men’s abilities vary; you would expect women to be underrepresented in quantum mechanics or navigation; though individual women may excel in these fields, women in general are unlikely to do so, for innate reasons. And vice versa with the low visibility of men in some fields.

The same is true of pay. The figures Harman has been discussing look depressing, but one ought not to rush into any assumptions about them. There are many explanations for women’s lower earnings besides unfair exploitation, and while any one case might be blatantly unjust – and employment tribunals exist to redress such inequalities – again it ain’t necessarily so. In some circumstances women may earn less than men for reasons that are not inherently unjust.

Women move in and out of jobs more. In devoting time to their families, they lose time at work to develop skills, not to mention experience and contacts, and in many careers that makes them less valuable as employees, with the result that in an equal market they might well earn less.

The only occupations to which it doesn’t much apply involve unskilled and semi-skilled work. For this reason it ought to be possible to ensure equal pay in this sector. It is a shameful thing that the long march towards equality for women has been forced into a dead end of institutionalised inequality for men.

minette.marrin@sunday-times.co.uk

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