## Facts

- In April 2010, Serdar Mohammed (SM), an Afghan national alleged to be a Taliban commander, was captured by British forces in Afghanistan during an ISAF operation following a lengthy firefight in which people were killed or injured.
- UK forces held SM in a British-run military detention facility in Afghanistan for over three months (about 110 days) before transferring him to Afghan authorities.
- SM challenged aspects of his detention under the Human Rights Act 1998 (HRA), relying on ECHR Article 5(1) (lawful deprivation of liberty only in specified cases and “in accordance with a procedure prescribed by law”) and Article 5(4) (right to take proceedings to challenge the lawfulness of detention).
- SM argued that he had no outside contact and no access to legal assistance while detained, so he had no practical means to seek habeas corpus or otherwise obtain an impartial and timely determination of the detention’s lawfulness.
- In the courts below, findings included that UK forces in Afghanistan had authority to detain for only a short initial period (treated as 96 hours) before transferring detainees to Afghan authorities; detention beyond that was held unlawful and incompatible with Article 5.
- The Ministry of Defence appealed to the UK Supreme Court. The Supreme Court issued two linked judgments on 17 January 2017: one addressing the main legal issues and another addressing consequential matters and the form of order.

## Issues

1. Whether SM was within the United Kingdom’s jurisdiction for ECHR Article 1 purposes while held in UK military custody in Afghanistan.
2. Whether, and from what source, UK forces had legal authority to detain SM beyond an initial period (including whether authority arose from Afghan law, ISAF arrangements, UN Security Council resolutions, or international humanitarian law (IHL)).
3. Whether UN Security Council resolutions authorising ISAF to take “all necessary measures” impliedly authorised security detention, and whether such authorisation could operate consistently with ECHR Article 5.
4. Whether ECHR Article 5(1) applied to the detention and, if it did, whether detention for “imperative reasons of security” could be treated as lawful where supported by the applicable international mandate and relevant legal framework.
5. Whether the available internal processes and practical ability to access a court satisfied ECHR Article 5(4)’s requirement of a speedy and effective review by a court or court-like body.
6. What consequential relief was appropriate, including whether damages might be available under HRA section 8 and what issues should be remitted for trial.

## Decision

- The Supreme Court held that SM was within the UK’s ECHR jurisdiction during the period of detention because he was in the physical custody and control of UK forces.
- The Court held that UK forces had power to detain persons in Afghanistan where detention was necessary for imperative reasons of security, and that this power could arise from the UN Security Council mandate for ISAF (including authorisation to take “all necessary measures”) read in its proper context.
- The Court rejected the contention that ECHR Article 5 was wholly displaced by IHL or by the UN mandate; the UK remained bound by Article 5 absent a valid derogation.
- The Court treated the UN Security Council resolutions as capable of being interpreted consistently with Article 5, and did not treat them as clearly requiring the UK to act incompatibly with Article 5.
- The Court held that the procedural arrangements available to detainees like SM did not satisfy Article 5(4): SM did not have a practical and effective opportunity to obtain a prompt, independent determination of the lawfulness of his detention.
- The Court’s orders (including those addressed in the second judgment) narrowed the legal disputes but left contested factual matters, and issues of remedy (including causation and quantum of any damages), to be resolved in further proceedings.

## Legal Principles

- A state has ECHR jurisdiction where its agents exercise physical custody and control over an individual abroad, including through military detention in an overseas facility run by that state.
- UN Security Council authorisation to use force and take “all necessary measures” in support of an international security mandate may, depending on context, imply authority to detain for imperative reasons of security.
- Any displacement or qualification of Convention rights by UN obligations requires clear conflict; where possible, UN Security Council resolutions should be interpreted so they do not require Convention violations.
- In armed conflict, IHL is relevant to interpreting Convention rights, but it does not remove Article 5 obligations in the absence of an Article 15 derogation.
- Article 5(1) requires detention to rest on a sufficiently clear legal basis and to be protected against arbitrariness; security detention must remain constrained by law and by the Convention’s minimum safeguards.
- Article 5(4) requires a real, timely ability to challenge detention before a body with judicial characteristics; a detainee must have practical access to a procedure capable of ordering release where detention is unlawful.
- Under HRA section 8, damages are available only if necessary to afford just satisfaction; entitlement and amount depend on the facts and are typically determined after trial where facts are disputed.

## Conclusion

In Serdar Mohammed v Ministry of Defence, the Supreme Court held that Article 5 applied to Serdar Mohammed’s detention by UK forces in Afghanistan and that the UN Security Council mandate for ISAF could provide authority to detain for imperative reasons of security, but it also held that the review arrangements failed to meet Article 5(4)’s requirement of a speedy and effective challenge to detention, leaving disputed facts and questions of remedy to later proceedings.


Serdar Mohammed v. Ministry of Defence, [2017] UKSC 1, [2017] UKSC 2 (2017)