On Thursday, the immigration minister was informed that his cleaner was an undocumented immigrant.

By yesterday afternoon he had resigned. Downing Street and the press like swift resignations. Thus far, the incident has been treated either as an ironic, it-could-have-come-from-The-Thick-Of-It joke or as a commendable example of Samurai-like honour.

Neither response is useful. In fact, Mark Harper's departure sets a dangerous precedent which ushers in a poisonous and authoritarian political climate.

Admittedly, it can be tempting to laugh. Harper's resignation is a meat-and-potatoes example of political hypocrisy, especially given his plans to force landlords, driving licence authorities, banks and GPs to turn into de-facto immigration officers.

But the predominant narrative has been the more sombre one. Most political commentators and fellow MPs have adopted a grave expression and spoken of an honourable man brought low by human error.

Even his Labour shadow, David Hanson, had kind words. "[Harper] has shown himself to be a decent man in his resignation and I wish him well for the future," his opposite number said.

David Cameron was quick to offer him a job." I hope very much that you will be able to return to service on the frontbench before too long," he wrote.

They usher him back in from the revolving door even as he swings it open. If only resignations outside of Westminster were so easily negated.

Of course, no such recognition of moral complexity was offered to his cleaner. This woman, who had worked for him since 2007, is now in the hands of immigration enforcement – typically a cruel and barbaric process of detention and deportation.

No-one will ask about whether she has a husband or children at home, or what they will go through if she is dragged away. No-one will ask about the friends she may have in her home country and what they will do without the remittance payments she may send home. No-one will ask anything about her at all. She is dehumanised, an object. Today's Sunday supplements will spend more time describing the characteristics of kitchen tables than the newspaper section spends on hers.

She is just part of the army of documented and undocumented immigrants, the people doing the toughest, dirtiest jobs, who you can see sometimes on buses at 4am, before anyone else is awake, being transported to offices they make clean for people in suits. It is the army of people which earns hardly any money, but still sends much of it overseas to support their friends and families; an army of people with just as many moral successes and failures as those who govern them, but who are treated not as humans but problems to be solved.

We should neither praise Harper's supposed-honour nor treat this resignation as a laughing matter. It is not. What Harper has done sets a perilous moral precedent requiring us to check the immigration status of others.

This, of course, is the logical end point of the culture Harper himself was trying to pass into law. The immigration bill, currently before parliament, believes the UK Border Agency to be so fundamentally incompetent that its functions must be outsourced to the civilian population. Your immigration status will be checked when you try to open a bank account, when you visit your GP, when you try to rent a home.

It is ID cards by the back door, except that this initiative has the advantage of also encouraging discrimination. On paper, it applies to everyone, but in practice it will be imposed most commonly on those who look like they might be foreign. Blacks, Asians and other minorities can expect to receive more demands for them to prove their status than white middle class families.

This is being pushed forward by the Conservative party, which likes to fool itself into thinking that it is committed to civil liberties. But it's not just them. The Liberal Democrats have been useless. Just three of them rebelled against the bill.

Labour has been mealy-mouthed about the proposals. "It is clear there are limits to the effectiveness of relying on employer and landlord checks to address illegal immigration," Hanson said. That's as robust as the opposition's objections get. Read it closely and you'll see this isn't really opposition at all. Hanson's amendments to the proposals call meekly for a pilot and more funding for an immigration status hotline. At best it's tinkering.

No amount of funding would do the job required of that hotline. Immigration status is a complex thing, not a binary choice between yes and no. It is often based on numerous applications on different statuses over a period of years. Requirements for one entry visa issued years ago will change midway through the period it applies to. Visas granted on one basis will contribute to a later visa granted on another basis. It is a supremely nuanced, myriad system of old and new rules falling over each other, policed by people who would not be considered top draw in any normal assessment of human capability.

Every week I receive emails and phone calls from people who have been denied visas on the basis of requirements which are irrelevant to their application. Often they are rejected for a different visa to the one they applied for. Several times, the Home Office seems to have no idea of what their nationality is when it makes the decision. The government takes literally years to make these infantile mistakes. Labour seems to think that a little bit of money will make an immigration hotline function in a preferable manner. It is wrong.

With his statutory programme in place, Harper's resignation will advance a cultural toxin: that it is a moral failure not to check the immigration status of those you employ.

Harper had not broken the law – not even the draconian laws he is trying to pass. He checked the immigration status of his cleaner when he employed her in 2007, then again when he became immigration minister in 2012. Then he checked a third time in 2013 and discovered that maybe the proof he had seen was not up to scratch. Even this level of surveillance – a level which would make general Franco blush – is apparently no longer enough to be an upstanding member of the government

Of course, his resignation was inevitable because the discrepancy between his political proposals and personal arrangements was so direct. But this increases the pressure on any minister to check the people they employ or are in contact with. And in a more general sense it increases the pressure on those in authority to always be aware of the immigration status of those around them.

Even those who lead the charge against immigration must be struck by the type of Britain we are creating, the type of place where people check your papers when conducting the most mundane of daily business.

This is as contrary to the decent characteristics of this country as could be imagined. For decades Brits have fooled themselves into thinking that they are impervious to authoritarian government because they are so averse to officialdom - to the jobs-worth, the curtain-twitcher, the nosey-parker, the bureaucrat.

How hollow that national characteristic appears now, when we are willing to sell it down the river to tackle a problem which anyway does not exist. After all, these measures are being adopted to kill off a process which contributes billions to our economy and without which we would be plunged back into recession.

Harper's resignation is not a laughing matter. Still less is it a question of honour. It is a dangerous precedent towards the creation of a more poisonous society.

Ian Dunt is editor of Politics.co.uk

The opinions in Politics.co.uk's Comment and Analysis section are those of the author and are no reflection of the views of the website or its owners.