And yet, despite all the legislation and subsequent case law, women in the UK are still paid on average about 20 per cent per hour less than men. Lawyers are no exception, with men earning about pounds 210 per week more than women, according to the 1996 New Earnings Survey.
Such inequalities have not gone unnoticed by the Equal Opportunities Commission, which is under a statutory duty to keep the Equal Pay and Sex Discrimination Acts under review. Hence its establishment of a code of practice on equal pay, the first of its kind developed by a member state in Europe, which came into force last week.
The aim is to "provide practical guidance and to recommend good practice to those with responsibility for ... the pay arrangements within a particular organisation". It provides an outline of current equal pay legislation for employers, along with an explanation of the main legal concepts and their implications for pay practices.
At the heart of the code lies an exhortation to employers to review their pay systems for sex bias, by way of a detailed, eight-stage process. This recommends a thorough analysis of the pay system, after which changes should be made to any rules or practices that have been shown to lead to discrimination. Employers should then monitor their pay practices and introduce a policy that commits them, among other things, to telling their staff how the pay system works and how their pay is calculated.
There is, however, no legal obligation on employers to adopt anything set out in the code. Its only relevance to a claim of equal pay or sex discrimination is that it can be admitted in evidence before an industrial tribunal. If the tribunal thinks the code is relevant to any of the questions arising out of the proceedings, it will be taken into account.
In other words, the code of practice has no standing in law. But Gary Bowker, editor of Equal Opportunities Review, points out that "it does provide additional protection to women in the sense that, when faced with an equal pay claim, the industrial tribunal can take into account the fact that the employer did not follow any of its recommendations". So although the employer does not have to comply with the code, failure to do so may have ramifications for his defence to a claim for equal pay.
Nevertheless, employers' organisations have welcomed the introduction of the code, with the Confederation of British Industry hailing it as "a useful and well presented guide for employers on a complex issue". Even the Federation of Small Businesses says it has "no problem with it", perhaps because the code recognises that "much of the detail and formalised procedures ... will not apply to small firms".
The code also has the support of the Government, although not necessarily of the Labour Party, which refused to be drawn on the subject. But whatever its views, it made no objection to the draft version which was laid before Parliament on 26 October last year by Gillian Shephard, the Secretary of State for Education and Employment. Commenting on the code, she said that the Government welcomed every effort to highlight problems of unequal pay. "The code will provide valuable guidance and encourage employers, whether small or large, to adopt good working practices."
A curious comment, given the degree to which the Government has been resisting the equal pay claims of 1,500 speech and language therapists over the past decade. After four appeals and a reference to the European Court of Justice, the lead cases are due to return to an industrial tribunal on 2 April, almost exactly 11 years after they were first submitted.
Sara Leslie, the solicitor representing the women on behalf of their union, MSF, thought it "ironic that the Government should have introduced a code of practice when it has been engaged in long-running litigation for 10 years with a female-dominated group who have valid claims". The applicants will be citing the code of practice in the tribunal in order to substantiate their claims, which are reckoned to be worth somewhere in the region of pounds 30m.
But despite the complexity of the existing legislation, there have been some recent successes, such as the 1,500 school meals workers employed by Cleveland County Council, who faced pay cuts following a compulsory competitive tendering exercise in 1994. They are celebrating a deal worth about pounds 4m, in what has been described as the biggest equal pay settlement ever.
Although the code is a step forward, some commentators maintain that Britain's equal pay legislation is still far from perfect. The EOC itself has tried over the years to persuade the Government to review and strengthen the Equal Pay and Sex Discrimination Acts, but with no success. It ended up in 1993, along with the TUC, making a complaint to the European Commission that the UK was in breach of EC law. They are both still waiting for a reply.
It is something of an understatement, then, when the code points out that "equal pay cases are extremely time consuming and expensive for employers". Which seems like a strong argument to introduce "systems which do not discriminate and are seen not to discriminate", but one which ministers have so far ignored.
The author is legal officer with the MSF union.