The controversial policy of detaining foreign terrorist suspects without trial was a key tool in preventing Britain from being attacked by al-Qa’eda militants, senior security officials believe.
The officials say that the emergency measure, introduced after the September 11 attacks on America, deterred scores of terrorists from entering the United Kingdom, and they fear that ending the policy will increase the chances of an attack here.
Charles Clarke, the Home Secretary, told the Commons last week that he was bowing to a law lords ruling to end the detention of foreign nationals suspected of threatening national security.
In future terrorist suspects, including those with British nationality, would be subject to a wide range of “executive control” orders, including house arrest and electronic tagging. The officials said they would have to “wait and see” whether the powers would be as effective.
One security official added, however, that the threat from terrorism was as “real today as it was in the immediate aftermath” of the World Trade Center attacks. He said: “The terrorists knew that they could be detained indefinitely and so in many cases they stopped entering the country. It was simple but effective.”