Jane thought she tasted something not quite right about that can of beans. But money was tight and she was hungry. So she ate some of it and became violently ill the next day. She kept the leftovers in the fridge but lacked the expertise or equipment to analyse it.

The Food Standards Agency had long since been abolished, so she would have to sue the manufacturer or the retailer of her contaminated supper by herself, without recourse to legal aid. This wasn’t realistic, so for several months many other people were poisoned too. A senior politician remarked that they should have used their “common sense” before eating the cut-price pulses. Jane received an equally dismissive reception when complaining about her unsafe rented housing and the chemicals that a multinational plant kept tipping into the nearby stream.

Then there was work. She had overheard enough conversations over the years to strongly suspect that the men were paid more. She spoke to her union rep, who was supportive, but she was put off by the need to stick her neck out, put her name to a grievance and maybe even sue her bosses, comparing the worth of her own contribution to that of male colleagues and friends. Not the easiest route to a quiet life.

The first paragraph of what I have written is pure dystopian fiction, if rooted in my reasonable fears about a future Boris Johnson Tory Britain with deregulation turbocharged by a trade deal with Donald Trump. The second paragraph represents the actual lived experience of many working women in Britain, whether poor or relatively affluent, professional, highly or less-skilled.

Next year will mark the 50th anniversary of Labour’s landmark Equal Pay Act, inspired by the women strikers at the Ford car plant in Dagenham, which put the great Barbara Castle in feminist history books forever; 2020 will also mark 10 years of the Equality Act, for which we have Harriet Harman to thank. That’s nearly five decades of legal obligations to pay women and men equally for equivalent work. I am a passionate believer in legislation but also in constantly reviewing and updating the law so that it never becomes a dead letter in a sealed book.

The Fawcett Society reports that the mean hourly gender pay gap is 13%. On this basis, next Thursday, 14 November, becomes Equal Pay Day, the day after which women in effect start working for free for the rest of the year. The society also projects that, at the current rate of progress, it will take another 60 years to close the gap.

So why has equal pay law failed to deliver equal pay for women up and down the land – from lawyers, bankers and journalists, to women working as cleaners, in hospitality and social care? The answer is enforcement.

How ridiculous. It’s as if individual pupils were left to sue their schools for not teaching them basic arithmetic, or patients had individually to verify the safety of prescribed medication before being able to trust it. Of course there have been high profile education and medical legal cases over the years, but the bottom line on regulation is that if society really cares about a standard – from schools and hospitals, to food, safety or the environment – the state takes responsibility for investigation and enforcement.

Some Conservatives and Liberal Democrats have grudgingly accepted moves towards equal pay auditing, but even inspection and audit is insufficient in the face of an intransigent employer.

That is why, as part of Labour’s radical “Women in the workplace” policy, we will amend the law to give a new Workers’ Protection Agency – supported by HMRC – powers to inspect, direct and if necessary fine employers who are failing to provide equal pay. No longer should individual women be left to tackle discrimination and injustice alone. We will join the top tier of nations taking radical steps towards equal pay.

Labour isn’t just the party of equality: it is also, crucially, the party of solidarity. Under Jeremy Corbyn’s leadership, a concept once dismissed as old-fashioned has come back into style. Solidarity encapsulates something very special about the human condition. We are independent and industrious individuals, but we are ultimately social creatures too. And that doesn’t just describe the place we aspire to live in – it shows us how to get there. I am proud of this historic Labour offer to the women of the United Kingdom. What was once fought for in Dagenham can finally be won everywhere.

• Shami Chakrabarti is shadow attorney general for England and Wales