The legal battle over the schemes has centred on claims brought by university graduate Cait Reilly, 24, from Birmingham, who challenged having to work for free at a local Poundland discount store and by 40-year-old unemployed HGV driver Jamieson Wilson, from Nottingham, who objected to doing unpaid work cleaning furniture and as a result was stripped of his jobseeker's allowance for six months. Ms Reilly, who was at the Supreme Court, said: "I brought these proceedings because I knew that there was something wrong when I was stopped from doing voluntary work in a local museum and instead forced to work for Poundland for free.
"I have been fortunate enough to find work in a supermarket but I know how difficult it can be. It must be time for the Government to rethink its strategy and actually do something constructive to help lift people out of unemployment and poverty."
Critics condemned the schemes as "slave labour" because they involved work without pay and cuts in jobseeker's allowance for those who failed to comply with the rules, while those in favour welcomed them as an effective way of getting people into employment.
Yesterday, Five Supreme Court justices upheld a Court of Appeal decision that 2011 regulations were legally flawed, but rejected claims that back to work schemes amounted to forced labour.
Since the Court of Appeal's ruling in February, the Government has fast-tracked new legislation, the Jobseekers (Back to Work Schemes) Act, through Parliament, which validates the 2011 regulations retrospectively.
After the latest decision in the legal battle, Phil Shiner, head of Public Interest Lawyers, said: "Today's ruling from the Supreme Court is of huge constitutional and practical significance. My firm will now get on with challenging, by judicial review, the retrospective legislation which was shamefully rushed through Parliament."
Responding to today's ruling, Mr Duncan Smith said: "We have always said it was ridiculous to say our schemes amounted to forced labour, and yet again we have won this argument."