Lone parents with children under two have won a High Court challenge against the Government's controversial benefit "cap" - with a judge ruling that "real misery is being caused to no good purpose".
The successful claim was brought over the "failure" to exempt them and their dependent babies and toddlers from the scheme along with a number of other groups.
A judge in London ruled on Thursday that he was "satisfied that the claims must succeed" against the Work and Pensions Secretary.
Mr Justice Collins announced: "Whether or not the defendant accepts my judgment, the evidence shows that the cap is capable of real damage to individuals such as the claimants.
"They are not workshy but find it, because of the care difficulties, impossible to comply with the work requirement.
"Most lone parents with children under two are not the sort of households the cap was intended to cover and, since they will depend on DHP (Discretionary Housing Payments), they will remain benefit households.
"Real misery is being caused to no good purpose."
He said the claim related to the "revised" benefit cap which "requires the parent in order to avoid the imposition of the cap to work at least 16 hours per week".
Lawyers for the four lone parent family claimants said after the decision was announced that the judge had ruled "that the application of the benefit cap to lone parents with children under two is unlawful because of its discriminatory impact upon children".
Rebekah Carrier, their solicitor, said in a statement: "The benefit cap has had a catastrophic impact upon vulnerable lone parent families and children across the country.
"Single mothers like my clients have been forced into homelessness and reliance on food banks as a result of the benefit cap.
"Thousands of children have been forced into poverty, which has severe long-term effects on the health and well-being."
She added: "We are pleased that today's decision will relieve my clients - and other lone parent families around the country - from the unfair impacts of austerity measures which have prevented them from being able to provide basic necessities for their children."