WHO, WHAT, WHY?
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One of the UK's top terrorism suspects is starting a new life beyond the razor wire of prison - within the walls of his own home. Is this house arrest?
Abu Qatada, Osama Bin Laden's "right-hand man in Europe"
The government views Jordanian cleric Abu Qatada as a dangerous man who once played a key role in linking extremist cells throughout Europe.
But he has been released from jail after the Court of Appeal ruled that he could not be deported to his home country.
While the case waits for its day before the House of Lords, Abu Qatada will be ordered to stay at home for 22 hours a day, along with restrictions including who he can meet and how he communicates with the outside world.
Control orders - including home curfews - introduced post-9/11
Restrict movements of terror suspects who can't be kept in jail or deported
But does this amount to house arrest? And if so, what does it actually mean in English law?
In most people's minds, the phrase "house arrest" prompts thoughts of dictatorships. Over the past year its appearance in Parliament has almost exclusively come in debates referring to Burma's long-suffering opposition leader Aung San Suu Kyi.
The most famous case in the UK was the 17 months spent by General Pinochet in the leafy surrounds of a luxury Surrey home as he battled against extradition to Spain.
But forms of home detention have increasingly become a key tool because of three inter-locking factors:
In the immigration system, home detention is key to dealing with some of those the government wants to deport - and this is why Abu Qatada is being subjected to 22 hours of curfew.
- immigration powers
- counter-terrrorism strategy
- tagging technology
Judges can order a highly restrictive curfew if the authorities want to deport someone from the UK, and they also have a realistic prospect of doing so. The complicating factor has been how these powers mix with counter-terrorism operations.
Aung San Suu Kyi has been under house arrest for six years
In the wake of 9/11, the government detained people in prison whom it accused of posing a threat to national security. Parliament brought in these unusual powers to deal with suspects ministers said they could neither deport nor prosecute.
But the Law Lords threw out that piece of legislation, forcing ministers to think again. Some of the detainees, who were released from jail immediately, went onto a 24-hour home curfew, very quickly replaced by the Control Order powers.
These powers are a civil measure rather than criminal punishment, designed to restrict the freedoms of a suspect to prevent them from doing something.
Control orders include long curfews in the home, regular contact with the police, restrictions on work or study, use of the phone, internet and whom someone could meet.
They're designed to restrict the movements of those where the authorities say they can't be kept in jail.
In the case of Abu Qatada, he was one of those released and put on a control order. The government struck a deal with Jordan saying it had a good chance to remove him from the UK, so he later went back into prison.
But they have objected to curfews longer than 16 hours because the suspect could be stuck indefinitely in that position - unlike immigration or extradition curfews, which are a stage on the way to deportation.
So are control orders house arrest? Judges have thrown out every attempt to have control orders ruled as illegal; they accept the need for some kind of house arrest.
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The issue is whether control orders and severely restrictive immigration curfews, like that now used against Abu Qatada, breach without good reason rights to a fair trial and liberty.
One judge, Mr Justice Sullivan, has described control orders as "the antithesis of liberty and more akin to detention in an open prison".
"They fall not very far short of house arrest, and certainly inhibit normal life considerably," he says.
Other judges have been more relaxed where officials have allowed the suspect a little latitude in their daily lives. The European Court of Human Rights, which includes UK judges, has gone further, ruling against a 24-hour curfew imposed on a Mafia don who was confined to a small island for 16 months.
But none of this means house arrest-like conditions are illegal - it's just that officials must prove to judges that there is a good reason to use such extreme measures.
But here is the problem with the Abu Qatada case. If the Law Lords rule that he cannot be deported, the government may not be able to request a 22-hour curfew anymore. They will need to prosecute him or place him under a control order again. The entire saga comes full circle.
Stay or go
So do we have house arrest or not in the UK?
General Pinochet spent 17 months under house arrest in Surrey
On the government side, it's not a term you will hear officials bandy around regularly - it has a slightly too emotional whiff about it for Whitehall legalese. But the reality is that they accept that it's widely used and is useful in demonstrating a tough position on difficult cases.
In the case of Abu Qatada and other suspects, the Home Secretary says that case is clearly made because how could such a dangerous man be allowed to walk the streets. It's not ideal, but it's the best of a bad situation, argue officials.
But Stephanie Harrison, a barrister involved in both control orders and tricky cases at the Special Immigration Appeals Commission, says that you can't call the conditions anything but house arrest.
"The regime is in place for a very long period of time - the experience is very destructive because every aspect of your life is controlled," she says of control orders. "It's a radical deviation from due process because the subject is neither a prisoner nor free person."
Compiled by Dominic Casciani