Kettling ruling due from European court of human rights The police power to contain large numbers of people at protests, the tactic known as kettling, could be called into question on Thursday by a ruling at the European court of human rights. The case has taken more than a decade to reach the court in Strasbourg and is the most significant among a host of legal challenges to the crowd control technique. Seventeen judges at the grand chamber of the court, which hears cases deemed the most important, will rule on whether four people swept up in a police cordon at Oxford Circus in 2001 were deprived of their right to liberty under article 5 of the European convention on human rights. All four were held against their will for up to seven hours in central London without access to food, water or toilets. The judgment has the potential to undermine what senior police believe is an essential tool for dealing with large crowds that become disruptive. Another judgment against the UK government would require a fundamental rethink of public order tactics less than five months before the Olympics. Common law precedent allows police to corral crowds into pens when they believe that doing so is the only way to prevent an imminent breach of the peace. Activists counter that kettling, which has become increasingly common since it was used to contain anti-capitalist demonstrators in 2001, infringes on the rights of peaceful protesters and amounts to a form of mass detention. Some experts argue that the tactic is counterproductive, inflaming crowds and encouraging confrontations. Kettling had been used occasionally before 2001 but police tended to disperse unruly protests or use small "snatch squads" of officers in riot gear to dart into crowds and pull out individuals identified as troublemakers. However, after two consecutive years in which anti-capitalist protesters were able to disrupt large parts of the capital, senior officers changed tactics in advance of May Day 2001. Borrowing a technique sometimes used to keep rival football fans apart, they encircled about 3,000 anti-globalisation demonstrators near Oxford Circus. Among those caught up was Lois Austin, now 42, one of the four applicants whose case is being considered in Strasbourg. Then a well-known activist, Austin was prevented from collecting her 11-month-old daughter from a creche. Since then, she has fought a 10-year legal battle against the Metropolitan police, in which she is seeking compensation for unlawful imprisonment. "This case could determine, once and for all, whether corralling people into police pens and coercively holding them for hours amounts to an unlawful deprivation of liberty," said her lawyer, Kat Craig from Christian Khan solicitors. The chief superintendent in charge of kettling Austin and others in 2001 is arguably the senior police officer who has most to lose if she wins her legal battle. Chris Allison has risen through the ranks to the position of assistant commissioner and is in charge of policing the Olympics. He said recently his officers were seeking intelligence about planned protests around the Games, and is unlikely to want any reduction in public order powers in the runup to the event. Kettling has become more frequent since 2009, when the law lords found against Austin and ruled that the Met had been acting lawfully in containing Austin because doing so was necessary to control some elements within the crowd who were committing violence. Although the ruling endorsed the Met's operation, the judges were careful to stress police must use the tactic in good faith, proportionately and for no longer than necessary. Recently, police have sought to provide temporary toilet facilities and bottles of water to crowds, and claim they show more discretion toward individuals who pose no threat or have a pressing need to leave a contained area. Kettling is now commonly used to manage protests by the English Defence League and counter-demonstrations by anti-racist groups. It has also been used - to varying degrees - at almost every large-scale demonstration in the past three years, despite warnings from crowd experts such as Dr Clifford Stott of Liverpool University that the tactic can sometimes escalate tensions, unifying a crowd in opposition to a perceived illegitimate use of force by police. The tactic was perhaps most controversially deployed at the G20 protests in London in 2009, where newspaper seller Ian Tomlinson died after being struck to the ground by a police officer. He had been struggling to find his way home through a succession of police cordons being used to kettle demonstrators around the Bank of England. Two months ago the court of appeal overturned a previous ruling by the high court, which had found the Met's containment of the climate camp sit-in at the G20 was unlawful. The claimants plan to appeal to the supreme court, but their case is one of a number that have been stayed until the completion of the human rights case. Other cases put on hold pending the judgment relate to containment at student fee demonstrations in late 2010, when police were criticised for holding schoolchildren late into the night in freezing conditions. The human rights case will rest on whether the judges agree with the applicants that being held in the kettle at Oxford Circus for seven hours constituted a breach of their liberty and, if so, whether it was lawful or justified In addition to Austin, the court has considered the cases of three bystanders who found themselves swept up in the anti-capitalist protests. They include George Black, now 62, who is represented by Liberty, who had been walking to a bookshop when he was swept inside the police cordons. Bronwyn Lowenthal and Peter O'Shea, now 40 and 48 respectively, both of whom are being represented by the law firm Bindmans, were office workers on their lunch-break when they were corralled into the kettle. May Day 2001 Thousands of anti-globalisation protesters are "kettled" at Oxford Circus in London. Lois Austin, who was held for seven hours, claims damages from Met for false imprisonment and breach of right to liberty. March 2005 Austin and a man caught in the kettle lose claim at high court. Mr Justice Tugendhat rules police had been "duty bound" to impose an absolute cordon to prevent violence and the risk of injury to persons and property. October 2007 High court ruling against Austin is upheld by appeal court. Master of the Rolls, Sir Anthony Clarke, says measures were needed for crowd's own protection. January 2009 The law lords rule against Austin but their judgment stipulates police must use the tactic proportionately. Austin appeals to European court of human rights. April 2009 Kettling is used extensively at the G20 protests in London, during which Ian Tomlinson, a newspaper vendor trying to find his way through police cordons, is unlawfully killed. Climate Camp activists bring a judicial review challenging the legality of one kettle. Late 2010 Thousands of students, some of school age, are kettled for hours in Westminster during demo against university tuition fee rises. The mass containment reignites the controversy over kettling and triggers a flurry of fresh legal actions against the Met. April 2011 High court rules the Met unlawfully contained Climate Camp activists during a sit-in at the G20 demo. Judgment deems the tactic had not been "necessary or proportionate." January 2012 Overturning the high court, the appeal court rules kettling was "least drastic" way of preventing what police reasonably believed was an imminent and serious breach of the peace. March 2012 Eleven years after Austin was kettled in Oxford Circus, the human rights court rules on her case and that of three bystanders who were swept up inside the police cordon for several hours. The legality of the tactic as well as a number of other pending court cases rest on the outcome.