The need for powers to hold terror suspects for more than 14 days in the future cannot be ruled out, the country's top prosecutor said today.
Keir Starmer QC, the director of public prosecutions, said suspects may need to be held for more than 14 days in "very challenging cases where there's a particular combination of circumstances".
Suspected terrorists have been held for more than 14 days in just three out of 38 terrorism cases over the last four years, Mr Starmer told MPs.
The extensions to pre-charge detention in these three cases were all necessary and nothing has changed to suggest this may not be necessary again in the future, he said.
Giving evidence to the Joint Committee on the Draft Detention of Terrorist Suspects (temporary extensions) Bills, Mr Starmer said: "Some contingency may be needed."
It was "impossible to define" the sort of cases which may require the extra time, he said.
"We can't find that piece of evidence to say, 'No contingency could conceivably be needed going forward'."
The last time suspects were held for more than 14 days was in June 2007, during Operation Seagram, the wide-ranging international investigation into the Glasgow airport bombing and the discovery a day earlier of two car bombs in London, Mr Starmer told MPs.
More time was needed in this case because of the different jurisdictions involved.
The other cases, both in August 2006, were during Operation Overt, the airline bomb plot which involved 24 arrests and a fear that there were more suspected terrorists still at large, and the case of Habib Ahmed and a Manchester-based al Qaida terror cell, which involved complex computer evidence which needed to be analysed.
Mr Starmer also said the admission of intercept evidence would assist prosecutions in the UK.
"The difficulties come with how you get intercept evidence to be evidentially admissible," he said.
Home Secretary Theresa May ended 28-day detention without charge in January, saying it was "one of the key issues that people are concerned about" in the review of counter-terrorism powers.
But emergency legislation is being drafted "in order to deal with urgent situations when more than 14 days is considered necessary, for example in response to multiple co-ordinated attacks and/or during multiple large and simultaneous investigations".
Mrs May also told MPs the Government was trying to find "a practical way" of using intercept evidence in courts to tackle terrorism and other serious crime and a report on a "legally viable model" was expected by the summer.
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