R (Das) v SSHD [2013] EWHC 682 (Admin), [2013] MHLO 28
"The Claimant's submission in these proceedings is that at the time of the second period of detention she suffered from a mental illness, in the form of depression and post traumatic stress disorder ("PTSD"), and that in detaining her the Secretary of State acted contrary to, or without having proper regard to, his own policy regarding detention of persons suffering from mental illness. This means that her detention was unlawful, as being in breach of the Claimant's legitimate expectation that the Secretary of State would take into account and abide by his policy in this regard. ... The Claimant is entitled to a declaration that the entire second period of detention was unlawful. However, she is only entitled to nominal damages for false imprisonment in relation to that detention."