In Hardial Singh the Administrative Court held that the statutory power to detain pending deportation, although unlimited on its face, was 'impliedly limited to a period which was reasonably necessary' and the SSHD had to show that he was acting expeditiously in progressing the deportation. Detention that exceeded such a reasonable period would become unlawful.

It was established in the Administrative Court in the case of Holgate–Mohammed that in order to prove that an arrest was lawful it was necessary both to show that there was a statutory or common law power to arrest, and that this power was exercised reasonably. It also established that a challenge to the reasonableness of the exercise of the statutory power could be brought in private law proceedings as well as by way of judicial review.

Ullah v Home Office - the Court of Appeal held that there could be no claim in false imprisonment for detention following the issue of a notice of intention to deport absent bad faith, even if the notice had been improperly issued.

The case of Chahal v UK - was heard in European Court of Human Rights on the application of a Sikh separatist leader who was detained for 6 years. The ECtHR found that his detention was not in breach of article 5(1)(f) and held that the Home Office was justified in detaining him as deportation proceedings were in progress and were being pursued with due diligence given the exceptional circumstances of the case. However the Court did state that the arrangements at that time for bail in national security cases breached article 5(4). This led to establishment of SIAC.

In the case of Tan Te Lam v Superintendent of Tai A Chau Detention Centre the Privy Council affirmed the principles set out in Hardial Singh, in ordering the release of Vietnamese boat people who had been held for 44 months as it could not be shown that removal was possible within a reasonable period of time.

In W v Home Office the Court of Appeal held that an immigration officer did not hold a duty of care in negligence to an immigrant in decisions made about their detention and so no claim for negligence could be brought for a careless decision making that led to further detention. The Court of Appeal did hold that loss of liberty could constitute ‘damage’ under the tort of negligence.

R v (1) Special Adjudicator (2) Secretary of State ex parte B - the Administrative Court granted a declaration that detention following a significant change in the strength of the asylum claim prior to eventual release was unlawful and that damages should be payable.

2001 - 2005 DS v Home Office was one of a series of damage settlements over these years in private law actions for those detained under the Immigration Act.

In R (Saadi) v SSHD the House of Lords held that a period of a week’s detention in the Oakington fast track for asylum applicants who were not considered to be at risk of absconding was not required to be 'necessary' for the purposes of article 5(1)(f) ECtHR. The detention was found to be lawful as it was for the purposes of preventing unauthorised entry and the 'short period' of detention was not found to be arbitrary. The ECtHR has declared this case admissible and so Strasbourg will examine whether detention for administrative convenience breaches Article 5.

R v SSHD ex parte I - in a further case applying the principles set out in Hardial Singh the Court of Appeal ordered the release of an Afghani national detained for 16 months after the conclusion of a criminal sentence.

In Nadarajah and another the Court of Appeal held that in order for detention to be lawful under the Immigration Act 1971 that it had to be in accordance with published policy. The policy and operational guidance to Immigration Officers is contained in Chapter 12 of the White Paper 'Fairer, Faster and Firmer – A Modern Approach to immigration and Asylum' published 1998, various subsequent parliamentary statements particularly relating to the Oakington fast track and Chapter 38 of the Operational Enforcement Manual ('OEM') and various Immigration Directorates’ Instructions.

A and others v SSHD - in the case of the indefinite detention of those suspected to be international terrorists the House of Lords held that that the UK’s derogation from Article 5 in the terms of the Human Rights Act 1998 (Designated Derogation) Order 2001 was unlawful and given that this was secondary legislation quashed the order. The House of Lords also declared that section 23 of ATCSA was incompatible with Articles 5 and 14 of the European Convention in so far as it was disproportionate and permitted detention of suspected international terrorists in a way that discriminated on the grounds of nationality or immigration status.

In ID and others v The Home Office there were a number of issues that were before the Court of Appeal. Firstly the Court was asked to decide whether a claim that detention was an unreasonable exercise of the discretion to detain and/or in breach of policy had to be brought in public law proceedings by judicial review rather than as here a private law damages claim. The Court of Appeal held that the relevant question under the Civil Procedure Rules was not whether 'the right procedure' had been adopted but whether the forum used deprived a party of the opportunity of having their case heard justly. Where the case was primarily about damages, and might involve cross examination and a jury private law proceedings were most appropriate. The Court held that the fact that the detention was carried out by a private contractor did not mean that the Home Office were not liable given that the detentions were caused by the immigration officers who authorised them. Lastly the Court of Appeal held that foreign nationals did not fall into a special category emphasising the particular importance that the law attached to the liberty of the person and that it was beyond doubt that the rule of law extended not simply to British nationals but also to immigrants subject to administrative detention.

Khadir – the House of Lords decided that whilst the power to detain contained in Schedule 2 to the Immigration Act 1971 is expressed as detention 'pending removal', that this did not mean anything more than 'until' removal, as long as there was some prospect of removal being achieved.

In Faulkner v SSHD the Administrative Court held that if the failure to give reasons for a Claimant’s detention under the Immigration Act resulted in prejudice that this rendered the detention unlawful.

R (Nampewo) v SSHD - the Administrative Court granted a writ of habeas for the Claimant who had been detained by Immigration Officers after having being granted bail by an Immigration Judge. The case was transferred for a hearing on the assessment of damages, in the event that these were not agreed.

R (Sow) v SSHD In another case of detention following the grant of bail it was accepted by the SSHD that detention was unlawful and the Claimant was released following an application for habeas and judicial review. The case was transferred for a hearing on the assessment of damages, in the event that these were not agreed.