A recent decision by the Administrative Court confirmed that it is not unlawful to force an individual in receipt of Job Seeker’s Allowance to participate in a 'work for your benefit' scheme, even if this involves unpaid work.
In this case, two of these schemes came under the Court’s scrutiny. The two individuals who were placed on each scheme argued that the choice of doing unpaid work or face losing their benefits amounted to slave labour and was a breach of their human rights. The Court, whilst refraining from commenting on the merits of such schemes, held that they did not amount to slavery or forced labour.
The full case can be found here (Case name: R (on behalf of Reilly & Wilson) v Department of Work and Pensions  EWHC 2292 (Admin)).