IN THE end, Big Brother was brought down by a Yorkshireman and a housewives’ league. When Clarence Willcock, a former Liberal Party parliamentary candidate, was pulled over for speeding in December 1950, he refused to produce his identity card, which had been introduced during each world war and kept after the second. “I am a Liberal,” he told the cops, “and I am against this sort of thing.” The High Court ruled against him, but commended his stand. Housewives burned their cards outside Parliament, and by 1952 they were scrapped.

But the “Englishman’s badge of servitude”, in the words of one late libertarian, is back. Tory and Labour politicians have been trying to reintroduce the cards for two decades. About 12,000 Britons were handed them under a phased roll-out in 2009, but the coalition government scrapped them a year later. The hounding of the Windrush generation of migrants who came to Britain legally but could not prove it felled the home secretary this week (see Bagehot). It has also rejuvenated the ID-card debate.

A clutch of ex-home secretaries claim such cards might have prevented the affair. One of them, Charles Clarke, says governments have three options to tackle illegal immigration. They can do little and hope for the best. Like the most recent governments, they can create a “hostile environment” in which landlords carry out immigration checks but citizens who lack paperwork struggle to prove their rights. Or they can plump for identity cards, which require a register of all citizens and would enable Britons to prove their identity and status. “Of the three, I think it wins by a mile,” he concludes.

How might a scheme work? There is no shortage of models for ministers to pinch. Every country in the European Union has a card, save for Britain, Denmark and Ireland. So do many others, though not America. Greece and Italy are swapping paper cards for plastic ones. Cards in a handful of other EU countries have no electronic chips. One former home secretary argues that technology has made physical cards obsolete. Instead, Britons could be given a unique number with which officials could access their data, as in Denmark. Some suggest adapting National Health Service numbers, which are already assigned to most people in the country.

European countries that deem plastic fantastic differ over who should carry it and when they should be required to flash it. Most insist every citizen has a card but nine, including France, do not. Belgians must carry theirs at all times, says Michel Poulain, a demographer. “When you go out you take your key, your money and your ID card. You don’t forget.” Labour’s scheme in 2009 would have made the cards voluntary for a decade. By then, most people would have applied for one anyway, reckons Alan Johnson, the home secretary at the time.

What sort of data should be linked to it? Health, tax and biometric data can all be joined. Estonians use their cards to access more than 3,000 e-services. Belgian councils keep more than 90 types of information about each cardholder, including whether they want to be buried or cremated. Ken Clarke, a former Tory home secretary, argues that a scheme might satisfy civil-libertarians if it did not become an “all-singing, all-dancing collection of data”. Safeguards would also help. In Estonia, powerful digital encryption guards against data breaches. In Belgium, civil servants who access data on the registry have their own ID numbers recorded.

Some argue that dishing out cards might in fact create more Windrush-style cases. Would the Home Office have given cards to the people caught up in the scandal? Mr Johnson says the scheme would need a lengthy roll-out period and for mandarins to take a generous, rather than hostile, attitude towards applicants without paperwork. Charles Clarke says a one-off amnesty could follow the launch.

Any attempt to introduce ID cards would be opposed by peculiar bedfellows. Liberty, a pressure group, is as implacably opposed as Jacob Rees-Mogg, an old-fashioned Tory who insists Britain is not “the sort of country that demands to see your papers”. Labour, like the Liberal Democrats, is now against the idea. Satbir Singh of the Joint Council for the Welfare of Immigrants, a charity, is ambivalent. His view partly rests on whether such a scheme would be administered by the Home Office. And he does not think a card alone would deal with the “culture of suspicion” that led to Britons being shabbily treated.

Still, the retired home secretaries’ chorus has won some converts. William Hague, a former Tory leader, agrees that the case for cards is now stronger. “We Conservatives were against this a decade ago, but times have moved on,” he wrote this week. Britain already issues migrants from outside Europe with ID cards in all but name, and might do the same for Europeans who stay after Brexit. Some say it would be fairer for everyone to get them.

Charles Clarke and Mr Johnson were among those given the cards in 2009. Mr Johnson still carries his in his wallet. Mr Clarke used to produce it at airports “just to prove that I could”. When the scheme was ditched, “they refused to refund me my £30, which I thought was tyrannical.” It could yet prove a long-term investment.