On Wednesday and Thursday, 5 and 6 May, a seven judge panel (Lords Phillips, Saville, Rodger, Walker, Brown and Clarke and Sir John Dyson) will hear the appeal in the control order case of AP v Secretary of State for the Home Department  EWCA Civ 731). The Court’s “Case Details” are here.
This is the latest in a series of control order cases in which the House of Lords and now the Supreme Court has grappled with the question of when restrictions on a person’s daily life become severe enough to amount to a ‘deprivation of liberty’ within the meaning of Article 5 of the European Convention on Human Rights.
Control orders were introduced by the Prevention of Terrorism Act 2005, as an alternative to the policy of detaining terrorist suspects without trial. The House of Lords found this policy of internment to be unlawful in its important decision in A and others v Secretary of State for the Home Department  2 AC 68. A person subject to a control order will not be detained in prison, but will be subjected to a package of measures which typically includes confinement to a specific address for many hours a day, as well as other intrusive restrictions on daily life. The 2005 Act envisaged that the government might in future try to ‘derogate’ from the right to liberty in Article 5 of the ECHR, so as to impose control orders which could not comply with Article 5. At present it has not done so, and all control orders must be Article 5-compliant. In practice, this means that the government cannot impose on a controlled person any measures which amount to a ‘deprivation of liberty’ within the meaning of Article 5.
In practice, it has proved extremely difficult to draw the line between measures which count as an unlawful ‘deprivation’ of liberty, and measures which amount to a mere ‘restriction’ on liberty, and are therefore not caught by Article 5. The House of Lords first considered the issue in JJ and Others v Secretary of State for the Home Department  1 AC 385. The majority – Lords Bingham and Brown and Baroness Hale – concluded that the measures in that case, which included an 18-hour curfew along with other severe restrictions on movement and social contact, amounted to a deprivation of liberty. They agreed with the first instance decision of Sullivan J that the right approach was to look at the concrete situation in which the whole control order regime placed the individuals concerned. Neither Lord Bingham nor Baroness Hale thought it appropriate to specify what length of curfew would amount to an acceptable maximum. Lord Brown, however, took the view that although 18 hours was too long, 12 or 14 hour curfews would be compatible with liberty, and 16 hours would be the ‘acceptable limit.’ In another control order case decided on the same day, E v Secretary of State for the Home Department  1 AC 499, the House of Lords held that a 12-hour curfew fell on the right side of the line. In the third case decided on that day, MB and AF v Secretary of State for the Home Department  1 AC 440, the House of Lords was primarily concerned with the question of fair procedures for those subject to control orders, but it also held that the 14-hour curfew imposed on AF did not amount to a deprivation of liberty.
Turning to AP’s case, his control order involves a 16-hour curfew and the usual range of other restrictions on daily life. Additionally, it requires him to live in a town approximately 150 miles from London, where he knows nobody, despite the fact that his family and friends are primarily located in north London. This has dramatically reduced his contact with his family, and created severe social isolation. At first instance ( EWHC 2001 (Admin)), Keith J concluded that the 16-hour curfew was not unlawful in itself, but the geographical separation from AP’s family tipped the balance:
“It is the combination of the equivalent of house arrest up to the maximum period identified by Lord Brown [16 hours], and the equivalent of internal exile which makes AP so socially isolated during the relatively few hours in the day when he is not under house arrest, coupled with his inability to make even social arrangements because pre-arranged meetings (otherwise than with his mother and his brother) are prohibited, which lead me to conclude that the obligations imposed on him fall on the side of the line which involves the deprivation of liberty rather than the restriction of movement.” 
This meant that the control order was unlawful. The Secretary of State appealed to the Court of Appeal, which allowed his appeal by a majority (Wall and Maurice Kay LJJ; Carnwath LJ dissenting,  EWCA Civ 731). The Court rejected the Secretary of State’s argument that the House of Lords in JJ had authorised all curfews of 16 hours and less. The curfew period could not be considered in isolation: the question was whether the impact of all the measures, taken as a whole, was severe enough to deprive the person of his or her liberty. While, as Baroness Hale said in E, ‘The starting point in any consideration of deprivation of liberty is the ‘core element’ of confinement’ , the whole picture must be considered, including the degree of social isolation experienced by the controlled person. Maurice Kay LJ put it concisely:
“for the purposes of Article 5, the other restrictions (including the degree of social isolation) are the tail; it is the core element of confinement that is the dog”. 
Where the majority thought that Keith J had fallen into error was in allowing the practical difficulties which AP’s family faced in visiting him in his new town. In effect, he had allowed an Article 8 consideration (interference with family life) to ‘trump’ a core Article 5 consideration (the need to ensure that AP did not maintain links with alleged ‘Islamic extremists’ in London). This was incorrect. Wall LJ considered that:
“There is, in my judgment, a substantial difference between taking ECHR Article 8.1 factors into account when discussing ECHR Article 5 on the one hand, and, on the other, of treating them as determinative of, or, as Maurice Kay LJ puts it, as ‘tipping the balance’ in relation to an Article 5 determination. In my judgment, the judge has done the latter, and it is principally for this reason that I find myself in respectful disagreement with him.” 
In his dissenting judgment, Carnwath LJ noted that, on the basis of the previous House of Lords decisions, a 16-hour curfew falls into a ‘grey area’ between the 14-hour period which was held to be lawful in AF, and the 18-hour period which was held to be unlawful in JJ. He considered that, in cases falling into this grey area, the Court of Appeal should take a “hands off’ approach to decisions of the judges of the Administrative Court, ‘who have to deal directly with cases in this difficult and sensitive area of the law.”  In respect of the Article 8 issues, he took the view that ‘in the light of the majority speeches in JJ it cannot be said that such factors are irrelevant to the judgment under Article 5. Within the grey area, the judge was entitled in law to take them into account.’ 
When considering AP’s appeal, the Supreme Court will have to consider, again, the extent to which it is prepared to give hard-edged guidance about the precise number of hours for which a person can lawfully be confined to their home. It will have to consider whether Lord Brown was correct to decide in JJ that a 16-hour period represents an ‘acceptable maximum’. It will also have to decide how ‘family life’ factors such as, in AP’s case, being required to move to a town 150 miles away, relate to the ‘core element’ of confinement, what weight judges are entitled to give them, and how much deference the higher courts should show to the decisions of the judges on the front line of these cases.
The fact that this is the fourth case at the highest level to grapple with the detail of control order requirements underlines the difficulties inherent in a scheme of intrusive measures which, quite deliberately, operate at the very limits of the right to liberty.