The upsurge in the use of anti-terrorism stop-and-search powers occurred as a direct result of the attempt to kill hundreds of people in the Tiger Tiger nightclub in London in 2007.

The bombers planted two car bombs near the club. When the devices failed to detonate, and realising that they were being hunted, they went on to ram a burning Jeep into Glasgow airport terminal.

Britain’s first serious terrorist attacks since July 2005 sparked a nationwide security operation. But because London, with its population, landmarks and international status, is one of al-Qaeda’s key targets, that security response was greater in the capital than everywhere else.

Its immediate form is high-visibility policing. That means yellow-jacketed officers flooding the streets and lots of people being stopped and searched. Under Section 44 of the Terrorism Act 2000 officers can stop anyone within a designated area without the requirement for reasonable suspicion. All of Greater London is such an area under an order renewed monthly by the Home Secretary. The police do not expect to find a bomb in every rucksack. But they know that al-Qaeda operatives make reconnaissance trips, take photos and test security.

The Met says stop and search is a vital tactic intended to “create a hostile environment for terrorists and provide a visible reassurance to the public”. The problem is Section 44 is a blunt instrument that antagonises as much as it reassures. The rise in the use of searches after the bombing attempt marked the number of black people stopped in London going up 354 per cent while the number of Asians searched tripled. The increase for whites was 295 per cent.

Section 44 is fast becoming a contentious issue for minority communities and for activists who say that it is regularly abused in the policing of protests.

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