So now we know. Back in August last year, I wrote a comment piece for the Guardian, focusing on the increasing noise about people being forced to work in return for their jobseeker's allowance – an idea whose roots extend well into Labour's time in government. It focused on two things: so-called mandatory work activity (MWA), whereby people are forced – via the threat of their jobseeker's allowance being suspended – to put in 30 hours a week doing work "of benefit to the community"; and other "work experience" schemes, in which people do up to eight weeks of unpaid labour, with one proviso: they can refuse to take part or pull out during the first seven days, but thereafter the work becomes compulsory, under pain of their benefit being withdrawn.

Yesterday, my colleague Shiv Malik pointed to the numbers of people involved in the scheme between May and November last year; 24,010 had done MWA, while 34,200 had participated in the second kind of work experience. The key revelation, though, was that in the last month for which there were figures, MWA numbers were outstripping those for non-compulsory(ish) work experience by 8,100 to 6,600. In other words, MWA seems to be mushrooming, along with its hardline sanctions regime: the first time you refuse to take part, you lose your benefit for 13 weeks; the second, for six months. Subject to the passing of the current welfare reform bill, rejecting MWA for a third time will mean no benefit for three years – and, one assumes, destitution.

At which point, it's worth pausing to reflect on what all this actually entails. Thanks to referrals by both jobcentres and private-sector Work Programme providers, it's about people effectively working for nothing, not only in charities and the public sector, but in huge retail chains. Thanks to the legal action launched by Cait Reilly, we all know about Poundland. Asda, Boots, Argos and TK Maxx, and the Arcadia group (including Topshop and Burton) are also involved. Hats off, perhaps, to Sainsbury's and Waterstones for announcing that they have ended their involvement with this kind of work experience, but if you want an indication that workfare may be turning into an immovable part of the private-sector economy, consider last night and today's blizzard of outrage about a Tesco ad placed on the Jobcentre Plus website. It's for nightshift workers in East Anglia, who will be paid "JSA plus expenses". In response, Tesco's Facebook page has been transformed into a glorious example of an online demo, brimming with anger. "I'll be boycotting your stores with immediate effect until you stop this exploitation – I will also be urging all my friends and family and contacts to do the same," goes one post. "No more Tesco for me until you withdraw from this government workfare scheme … It is compulsory forced labour," says another. The company are trying to keep a lid on it all, with little success: "You can delete as much as you like but this will now go viral," offers one poster.

On Twitter, Shiv Malik revealed other adverts for similar roles at Tesco, and Tesco's explanation shifted. As Left Foot Forward reported this morning, their initial line was that they "are taking part in a government-led work experience scheme to help young people" which "has already led to 300 permanent jobs". They then put the advert down to "an error made by Jobcentre Plus" and claimed that it should have been "for work experience with a guaranteed interview at the end". As far as I can tell, they still want to employ nightshift workers for nothing.

Whatever the answer, the crucial point is that unpaid work – bad enough when it applied to supposed "interns", but grim beyond belief when used on the unemployed – is now being built into what some people call The New Normal. Given the thousands involved, it clearly represents a boon to the kind of multinational giants whose profit margins must be creeping upwards thanks to the plentiful supply of people – and please, all you free-marketeers, read this bit slowly – effectively paid a pittance to work for them by the taxpayer. Note also the way that even more sinister aspects of all this are pointed up by the breakdown of people who've done work experience, as opposed to MWA: 13% of work experience "participants" are from ethnic minorities, but when hardened compulsion is used via MWA, that number rises to 24%.

Last year, a Department for Work and Pensions spokesperson told me the "community benefit" meant that MWA would be kept out of the private sector – but on the ground, that doesn't seem to be working, at all. Now the DWP claim only that they "expect that every placement will offer people the opportunity to gain fundamental work disciplines, as well as being of benefit to local communities". Also, if you still think that all this denotes only short-term arrangements that aren't an offence to public morals and shouldn't be too onerous for anyone, consider one of the more overlooked aspects of current welfare-to-work practice: something called the community action programme, under which people are mandated to work for their benefit for up to 26 weeks. That's six months, to you and me. Such outrages continue to be rolled out at speed; the horror is only compounded by how little attention mainstream politics continues to give them.

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