Background
Rosina Davis sought judicial review of her detention at Heathrow Airport for 30 minutes on 20 August 2023. She advanced three main challenges: (1) that the policy governing short-term detention of those with limited leave to remain was unlawful; (2) that the policy was unlawful because unpublished; and (3) that the detention breached Articles 5 and 8 of the European Convention on Human Rights. She also argued the Home Office remained in breach of the public sector equality duty following an earlier finding in R (MXK and SSB) v SSHD [2023] EWHC 1272 (Admin).
The main judgment was handed down on 3 June 2026. Davis succeeded on two grounds but failed on the policy and human rights challenges. Following partial success, the court invited submissions on costs. The claimant sought 75% of her costs; the defendant contended for 40%.
The Court’s Holding
Justice Cavanagh held that the defendant should pay 50% of the claimant’s costs. Although Davis obtained an order that her detention was unlawful and recovered £2,250 in damages for false imprisonment, this was “far from being a total victory.” The primary battleground—whether the detention policy itself was unlawful—resulted in complete failure for the claimant, consuming substantial court time and complex legal argument.
The court applied the broad-brush approach mandated by CPR 44, weighing that Davis succeeded on discrete, relatively straightforward issues (the 30-minute detention and equality duty, the latter already established in prior case law), against her failure on the major policy and human rights challenges. While the defendant had changed position during proceedings, the claimant had already recovered costs thrown away from an earlier order. The 50% award reflected fairness to publicly funded legal practitioners without elevating unsuccessful ancillary arguments.
Key Takeaways
- Partial success in judicial review justifies proportionate costs awards; a claimant who loses on the main issues faces costs reduction despite winning on subsidiary grounds.
- Court time consumed by unsuccessful arguments, particularly complex legal submissions that would not have been necessary for narrower claims, significantly influences costs apportionment.
- Pre-existing case law establishing breaches (here, the equality duty finding) may reduce time and costs attributable to those issues at trial.
- Courts consider the impact of costs orders on publicly funded legal practitioners when setting proportions, but this does not override the need to penalize unsuccessful major contentions.
Why It Matters
This ruling illustrates how UK courts balance competing considerations in costs awards for mixed-success judicial review cases. Although Davis achieved her immediate goal—establishing unlawfulness and securing damages for 30 minutes’ detention—her failure on broader policy and human rights grounds meant the overall claim was not substantially successful. The 50% award reflects that much of the evidence, legal argument, and court time would have been unnecessary had the case been confined to the narrow detention issue.
For legal practitioners in immigration and public law, the decision reinforces that costs awards follow the contours of success. Collateral arguments, however intellectually interesting or broad in public significance, will not insulate a claimant from costs consequences if the central claim fails. The court’s acknowledgment of the publicly funded context shows judicial awareness of sustainability pressures on legal aid practitioners, but operates as a ceiling, not a guarantee of full recovery.
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