Campaigners say disabled people are being unfairly targeted and living in 'fear of the brown envelope' thanks to mysterious computer processes that the government has never fully explained.
The Department for Work and Pensions is facing fresh legal action to reveal what “algorithms” it uses to flag claims of benefit fraud.
The Greater Manchester Coalition of Disabled People has sent a “letter before action” demanding ministers “come clean” about techniques it claims is throwing disabled claimants into crisis.
The campaign group says disabled people have had questions raised over their benefit claims through a phone call, e-mail or “brown envelope” in the post without knowing why.
Sometimes they have essential cash “cut off” at the beginning of probes that can last over a year, the group said.
GMCDP spokesperson Rick Burgess said benefit claimants of all stripes are singled out, but campaigners believe the algorithm is “over-picking disabled people for investigations of fraud”.
He told a meeting tonight: “You have no idea how it came about that you’re being investigated - none whatsoever.
“It’s extremely upsetting when people get this.”
He added: “We are living in a shadow penal system that treats us like criminals for having to meet the same needs as everyone else. The fear of the brown envelope makes disabled people feel terrorised, in a constant state of anxiety and on edge.”
It is the second legal letter sent by the same group on the subject, with the first going out before Christmas.
The DWP responded in December, but the group alleges the government has still not answered key questions about what technology it uses to flag possible fraud.
The fresh legal letter - to which the DWP must respond in 28 days - challenges the “use of AI, algorithmic technology and other forms of automation” in investigation of benefit fraud.
It says the DWP uses “data matching” and “machine learning”, but other techniques may be being used and the DWP is not being clear about what they are.
The letter says there is a “risk of bias” to automated processing.
It demands the DWP set out “detailed information” on its use of computer processes and sets up “adequate safeguards”.
Barrister Will Perry, who is representing the legal action supported by the “tech justice” group Foxglove and Privacy International, said: “We know there is a data matching algorithm being used.
“The DWP seem to be experimenting with a wide range of different technologies.”
DWP Permanent Secretary Peter Schofield has previously insisted computer systems “guide our work” but “we do not take any action against anyone based on a machine.”
He added: “It always comes down to an individual.”