Tenants with one spare bedroom have had a payment reduction of 14% and those deemed to have two or more spare a reduction of 25%.
Lawyers for the 11 cases say that, unless the families move from their homes into smaller properties, they face building up rent arrears and being forced out any way.
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After Roy Hodgson's resignation following England's humiliating exit from Euro 2016, who are the leading contenders to replace him?
The beleaguered Labour Party leader is clinging onto power in the face of as many as 150 MPs voting to remove him from the top job today.
Mr Osborne said he is "not the person to provide the unity my party needs".