In 2015, following evidence and criticisms from a range of organisations and individuals including under-cover film from detention centres, the Home Secretary commissioned Stephen Shaw (former Prisons Ombudsman) to carry out a review into the welfare in detention of vulnerable persons. The Shaw Report was published in January 2016. Testimony from Asylum Welcome is cited the report. The report concludes:
“I my view, a smaller, more focused, strategically planned immigration detention estate, subject to the many reforms I have outlined in this report, would both be more protective of the welfare of vulnerable people and deliver better value for the taxpayer. Immigration detention has increased, is increasing, and – whether by better screening, more effective reviews, or formal time limit – it ought to be reduced."
You can read the full report (which includes an executive summary) https://www.gov.uk/government/publications/review-into-the-welfare-in-detention-of-vulnerable-persons
and Asylum Welcome’s submission