The home secretary is proposing a change in the law to allow phone tapping evidence to be used in court. BBC News Online asks is this a vital and overdue measure in the fight against terror? Or is it an erosion of our civil liberties?
By Tom Geoghegan
BBC News Online
At present recordings from telephone intercepts carried out by the police and the security service can only be used for intelligence purposes.
But a government review is considering whether such material should be admissible in criminal trials of terror suspects.
This is a move supported by some senior police officers and prosecutors because it would help them prove their case.
WHO'S ON THE LINE?
The home secretary must authorise each phone tap
He issues a warrant under conditions of the Regulation of Investigatory Powers Act
There were 1,885 taps in 2003
Other methods of covert surveillance are admissible in court
When asked if he favoured such a move, the Home Secretary David Blunkett said there would need to be measures in place to protect the "sources" of the conversations from exposure.
"If we can square that circle, then within limited circumstances we would be willing to do so," he told BBC's Newsnight.
Charles Shoebridge, former anti-terrorist officer, believes phone tapping should be introduced in such cases.
He told BBC News Online: "There are a number of cases from the past where this evidence, had it been admissible, could have led to convictions of terrorists who were not convicted.
"Clearly, any measures that help the police and security services carry out their tasks without endangering the civil liberties of everyone else are to be welcomed.
"If particular measures can be introduced to enhance effectiveness, it may be there's less need to introduce legislation which may be of less help but could impact on the civil liberties of many."
The Crown Prosecution Service, which is involved in the review, has previously admitted the move would aid prosecutions but acknowledged the doubts held by civil liberty groups and senior intelligence officials.
Members of the intelligence community have in the past expressed concern that the divulgence of phone tapping evidence may alert criminals to the methods used to catch them.
Simon Davies, director of surveillance watchdog Privacy International, told BBC News Online it would be "disastrous" for justice.
He said: "I'm worried what will eventually occur by creep is that phone evidence will be admitted to a jury - already overwhelmed by directions - as if a matter of fact.
"There's a difference between what's said in a phone call and what's investigated by police and presented in court.
"Currently, if the police can't collect 'first generation' evidence deduced from a phone call then that information cannot be admitted."
A confession of guilt would still have to be backed up properly by police investigations, he said.
So the only value of tapping tapes could be to establish if two people were associated.
Mr Davies said Mr Blunkett's plan could be further evidence of "exemption creep" when an initiative is introduced in limited circumstances and then widened, like the DNA database.
Blunkett believes phone bugging evidence could help fight terror
But Barry Hugill, spokesman for civil rights group Liberty, told BBC News Online: "We don't in principle object, provided it's admissible in a court with a properly constituted jury.
"It's important the defendants have the right to cross-examine that evidence."
He said the "kangaroo courts" used for the 14 terrorist suspects held in Belmarsh prison under emergency legislation did allow phone bugged evidence.
Mr Hugill objected to the fact these men were not permitted to see or respond to this evidence.