WESTMINSTER must take responsibility for the Concentrix “shambles” which has left thousands of families cut off from tax credits, MPs said yesterday.

Members from across the Chamber said government officials must admit it helped cause the scandal which has seen single mothers accused of having relationships with dead people, strangers and members of their own family.

The American-owned company won the contract to help cut the benefits bill by more than £1 billion by weeding out fraudsters. The deal was struck on a performance basis, with Concentrix set to be paid in accordance with its results.

MPs from all sides told how their constituents had been forced to turn to food banks to feed their families after Concentrix wrongly accused them of lying and stopped their payments.

Branding it a “shambles”, Paisley and Renfrewshire South MP Mhairi Black said: “The buck has to stop with HMRC.

“The Government has to bring this sort of thing back in house.

“You can’t say to a private company ‘we want you to make £1bn worth of cuts but we are only going to pay you on a results basis. That is a recipe for disaster.”

Black, who sits on the Work and Pensions Select Committee, said Concentrix was ignorant of basic arrangements in Scotland, struggling with flat numbers and mistaking newsagent chain RS McColl for an adult involved with parents in several locations.

She said: “It’s truly the most ridiculous level of incompetence I’ve ever heard.

“People were accused of being in relationships with dead tenants 70 years their senior. They were accused of being in relationships with some of their own children.

“In my constituency, Scottish flat numbers seemed to be a major cause of issue for Concentrix because they couldn’t get their head around the fact that flat 1/1 and 1/2 were across the landing from each other and they weren’t the same house.

“The best one has to be the case of RS McColl. RS McColl is a corner shop in Scotland that is as common as a WH Smith is in England and yet people were being accused of living with this mysterious Mr McColl because their flat was above an RS McColl shop.

“At no point did anyone in

Concentrix or HMRC think, ‘wait a minute, this Casanova is getting about a bit’.

“This would be funny until we remember that this is actually people’s lives, this is their survival we’re talking about.”

Labour’s Rebecca Long Bailey told how one mother-of-three had waited months for her payments to be reinstated after being accused of living with another woman, existing only on maternity allowance granted for her newborn during that period.

Stretford and Urmston MP Kate Green said a family in her constituency sent their children to live with relatives because their mother could not feed them or heat their home.

Jane Ellison, Financial Secretary to the Treasury, said most cases should be looked at within four days, but “complex” examples may take longer.

She said 181,000 incomplete cases had been taken on by HMRC, with only two per cent of these still to conclude and the rest completed within a month.

Some 26,000 requests to review decisions were received and £100 hardship payments were made available to those affected.

However, MPs heard this could trigger an overpayment and leave claimants facing orders to pay money back.

Ellison, who said lessons would be learned by the Government, said tax credits fraud was now at its lowest level since 2003 and some of the problem claims were caused by people getting “muddled up” with their forms.

She said: “It is a complicated system which it’s very easy for many honest people to get wrong.”

However, Black said the Government must acknowledge its role in passing the details of potential fraudsters to Concentrix for investigation, adding: “When mistakes are made by government, it is the people who suffer. The Government has to bear some of the burden for this.”

Awarded in May last year, the

Concentrix contract was worth up to £75m.

In September the Government announced it will not renew the contract.

At the time, a spokesperson for the company said: “We have operated professionally at all times and within the guidance set by HMRC.

“The HMRC statement not to renew the contract attacks our professional credibility, and the commitment of our staff who have performed determinedly, despite the issues with HMRC policies and procedures.

“Through the term of the contract we are pleased to have saved the taxpayer nearly £300m in authentic confirmed tax fraud and error which otherwise would have cost the taxpayer money.”