Forty years ago, a group of women sewing machinists at the Ford Motor Company plant in Dagenham saw red. They discovered that men who were doing the same work as them - making the car seats for Cortinas and Zephyrs - were being paid 15 per cent more.
The women walked out of the plant on 7 June 1968 in support of a claim that would not only pay them the difference but that would recognise their skills and put them on a higher grade. Many of them were former dressmakers and took pride in their work which they felt was going unrecognised. They wanted to be put on the same pay level, grade C, as the paint spray operators in the plant. As this was the group of machinists responsible for making all the seat covers their action rapidly brought production at the plant to a halt.
One of them, Violet Lawson, recalled last week: 'At that time we had men night-work machinists and they were getting paid more than us. And we said, "Well, we want C grade if the men are getting it. We want equal pay".'
After three weeks of a very high-profile strike, they settled for 92 per cent of the C grade rate. Barbara Castle, the formidable Labour employment minister of the day, was brought in to help negotiate a settlement.
But the impact of the walkout was far-reaching. It hastened the government to bring in the Equal Pay Act in 1970, which for the first time made it illegal to have a separate pay rate for men and women. It also set out the concept of 'like work' so that those whose work was rated as equivalent to another job, but were paid less, could go to a tribunal.
Forty years on, many campaigners are asking why it is that men and women are still paid such different rates. The UK is one of the worst in Europe in terms of the gender divide, with women in full-time work being paid, on average, 17 per cent less than their male counterparts. When it comes to part-time work, the figures are much worse. The gap is enormous - a 36 per cent gap between the sexes.
There has also been a huge rise in the number of legal cases. Last year, 44,000 equal pay claims were brought before the courts, more than double the number in 2005. Very few make it through to an employment tribunal - some women give up and many others settle out of court, with companies often demanding that employees sign a confidentiality clause.
The full-time hourly gender pay gap of 17 per cent appears to rise to 22.3 per cent in the private sector (compared to 13.4 per cent in the public sector), according to the Office of National Statistics. Although there has been a tiny decline of 0.3 per cent between 2006 and 2007 in the pay gap, there is enormous frustration that companies are not doing more to narrow it. One of those most involved in trying to push forward the issue is Trevor Phillips, who chairs the Equality and Human Rights Commission.
He told The Observer: 'At the current rate, it will take at least another two decades to close the pay gap. Women who work full time will earn on average £330,000 less than a man over their working lives - that's the price of a family home. It's amazing we still think this is something that a decent society can live with.'
He said: 'First, we need to attack the secrecy over pay, so woman aren't forced to take legal action just to find out if they're being treated fairly. Second, we need to get the creaking tribunal system working again so that women can get some justice right now, instead of having to wait decades.'
But Phillips would also like to see more women realising that they can bring claims and that there are laws and organisations to support them. He said: 'The sewing machinists paved the way for equal pay legislation that brought welcome change for thousands of women. Forty years ago job advertisements regularly featured different rates for men and women. This is now unthinkable. The women remain an inspiration to us today and we need to retain that spirit.'
Thousands of cases now centre on women doing predominantly female jobs comparing themselves with men doing traditional male work at a similar level, or of a similar value. One of the reasons for the pay divide is that women who have children go into lower paid work such as catering or childcare, even though it is of equal value to traditionally male jobs such as drivers or street cleaners.
Ministers, deeply aware that there is growing anger among women at the pay gap, will soon be producing the long-awaited Equalities Bill. However, there is concern among campaigners that there will be very little in it about strengthening the case for equal pay. A combination of factors, such as a worsening economy and new rights for agency workers, have made it less likely that the equalities minister Harriet Harman will push for strong measures, such as an obligation on companies to carry out mandatory pay audits.
A government spokeswoman said: 'It is unacceptable that the gender pay gap still exists nearly 40 years after the Equal Pay Act. We need to improve transparency so that women can know if they are paid fairly and so we can see where more needs to be done. Final decisions are yet to be made, but we are closely considering a number of strong measures for the Equality Bill.'
A European ruling in 2004 entitled women who had been found to suffer pay inequality to six years' back pay, unleashing an avalanche of claims. Local authorities and other public sector employers now face massive increases in their wage bills and claims for back pay following legal rulings that affect thousands of low paid women who work in jobs such as cleaning or as dinner ladies.
One of those is Kathleen Cunningham, 44, who is still fighting her case against the council in Bury, Greater Manchester. She worked at a school as a cleaner and as a midday supervisor for six years until 2006, bringing home around £180 a month.
'I actually found out from a neighbour that there was a big issue around equal pay claims against the council,' said Cunningham. She is now fighting her case in the legal system, on the basis that her 'comparator' - a male street cleaner on the same grade - would be receiving an annual bonus of around £4,000 a year, which she missed out on for six years.
Sarah Veale, head of equality at the TUC, said the present system meant individual women bringing a case, rather than a ruling which helped the whole group. 'Low-paid women have to stand in a queue which can take years and, to my mind, it's a totally flawed way of dealing with it.
'The other problem of course, is that women's jobs are just paid at a much lower rate, so a car mechanic will typically be paid more than the woman who works in a nursing home. Because of the culture we have, women tend to put up with it, and it becomes a self-perpetuating system, so that women are also less likely to get on in their careers.'
The whole issue of equal pay in councils has already prompted strikes in Birmingham, and unions accept that there is a fine line between preserving pay and keeping jobs. A series of such cases is now clogging up the tribunal system. Some fear the estimated 50,000 claims waiting to be heard could soar to perhaps 150,000 by the end of the year.
Many of the cases that hit the headlines involve high-earning City workers who find they are discriminated against. In 2002, Julie Bower, a former Schroders analyst, won £1.4m for sex discrimination. A tribunal was told how her bonus of £50,000 was a fraction of those paid to male colleagues performing to a similar standard.
Last year, at one of the major investment banks, a 24-year-old female trader found out that she was being paid less than the man who had just been hired to sit at her desk.
Clare (not her real name) believed her bosses were not operating a level playing field. 'I wasn't paid a pay rise that had been promised to me, and I wasn't given a bonus I had earned, although they disputed this. I was working long days, and most weekends, and yet I was treated as a second-class citizen.'
But when she filed a grievance, they responded by bringing disciplinary charges against her. With the help of lawyers she won compensation, but is still finding it hard to get back into work. 'It does really knock your confidence to go through this kind of case. I think pay discrimination is probably widespread across the City, but there is this enormous secrecy surrounding salaries and bonuses. And if you complain, you are seen as a troublemaker and not one of the "boys".'
One of those who has been through the highly stressful situation of having to fight her corner is Bridget Bodman, a former accountant at manufacturing company API Group. She was appointed as a group accountant in 2000 and promoted to financial controller a year later. But she questioned the salary and benefits offered to her male replacement and asked the company to complete an equal pay questionnaire. It emerged that her successor was paid £8,000 more and received an £8,640 car allowance as well as additional benefits.
'The company didn't have many senior women, which I think was part of the problem,' said Bodman. 'There was absolute shock and horror that I could even suggest that there might be some form of sexism operating. They became very angry and very cross and then I had to decide whether to back down or carry on fighting.'
Bodman fought the case all the way to an employment tribunal and received £25,000 compensation in November 2006 in a case supported by the former Equal Opportunities Commission, one of the bodies to be merged into the Equality and Human Rights Commission.
The tribunal's ruling was important. It stated that 'the absence of both clear criteria and process for determining pay awards and bonus payments creates a climate where pay discrimination on gender grounds can operate, consciously or unconsciously, unsuspected, undetected and unchallenged'.
Bodman, who is now bringing up her children in New Mills, Derbyshire, said: 'I'm glad I fought the case, although it was very stressful. At first, when I realised there was this pay divide, I went through a lot of doubts - was I not good enough at my job, maybe there was a genuine reason. But then I realised that it wasn't right and that I had to make a stand. Hopefully it will set a good precedent for other women, although I find it amazing that in 2008 this kind of discrimination is still happening, and on such a wide scale.'
· This article was amended on June 8 2008. We used the term 'industrial tribunals'. They became employment tribunals in 1998. This has been corrected.
