The Court of Appeal's unanimous decision against discount store Poundland is a "huge setback for the Department for Work and Pensions (DWP), whose flagship reforms have been beset with problems since their inception", according to Public Interest Lawyers.
The lawyers, who represented Cait Reilly and 40-year-old unemployed HGV driver Jamieson Wilson, said that "until new regulations are enacted with proper parliamentary approval, nobody can be compelled to participate on the schemes".
Today's judgment sends Iain Duncan Smith back to the drawing board to make fresh regulations which are fair and comply with the court's ruling.
Until that time nobody can be lawfully forced to participate in schemes affected such as the Work Programme and the Community Action Programme.
All of those who have been stripped of their benefits have a right to claim the money back that has been unlawfully taken away from them.
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The major party leaders' campaigns for the General Election will remain suspended on Wednesday following the Manchester terror attack.
Thousands of people have donated to help the families of the victims - as well as a homeless man who came to their aid.
Some children, particularly those who have been more directly affected, may show symptoms of stress and trauma.