R (Lumba (WL (Congo))) v Secretary of State for the Home Department [2011] UKSC 12; [2012] 1 AC 245

D, the Home Office, published a policy that concerned detaining foreign national prisons which stated, in cases of immigrants that are placed in detention and are awaiting deportation, that there was a presumption favouring their release. D chose to follow an unpublished policy which was in complete contradiction to the above policy described. The policy involved a ban on the release of immigrants. Cs, who were prisoners, applied for judicial review of the unpublished policy which sought to create a blanket ban on the release of the detainees. Cs also sought to sue D under the tort of false imprisonment.

Whether detention pursuant to an unpublished policy inconsistent with the published policy was unlawful, and how that unlawfulness affected the entitlement to damages for false imprisonment.

The Supreme Court held that the relevant detention decisions were unlawful because the Home Office had applied an unpublished policy materially inconsistent with its published approach. The existence of a broad statutory power did not justify detention reached through that unlawful policy. The majority also rejected a defence that the claimants would inevitably have been detained if a lawful decision had been made. That counterfactual was relevant to damages, however: where no loss beyond the lawful detention was established, only nominal damages were appropriate. The Court did not recognise a separate award of vindicatory damages for the violation. The judgment therefore separates transparent exercise of discretion, liability for false imprisonment and compensation for resulting loss.

Detention under an unlawful unpublished policy is not justified merely because lawful detention could have occurred. Lumba distinguishes false-imprisonment liability from damages: inevitable lawful detention can limit compensation to nominal damages without making the actual detention lawful.

Lumba links transparent detention policy with individual liberty and the tort of false imprisonment. A secret, materially different policy cannot be excused simply by showing that lawful detention might have been possible. The possibility of lawful detention instead affects compensation. The decision distinguishes the wrong itself from consequential loss and rejects an additional vindicatory damages category in this setting. The record retains its historical WL (Congo) URL, but the case is commonly cited as Lumba and that identity should be clear to students.