By Dominic Casciani
BBC News home affairs reporter
Sir Ken Macdonald QC warns against over-surveillance
The outgoing chief prosecutor for England and Wales has warned against a security state amid fear of terrorism.
Sir Ken Macdonald QC warned against "the paraphernalia of paranoia" and "medieval delusions".
The outgoing director of public prosecutions gave his warning after the home secretary proposed a database for mobile and internet traffic.
But in his final speech, Sir Ken called for "level headedness" and restraint to uphold hard-won freedoms.
"We need to take very great care not to fall into a way of life in which freedom's back is broken by the relentless pressure of a security state," he said.
The former defence barrister said his period at the top of the Crown Prosecution Service (CPS) had been a "relentless prosecutorial struggle against terrorism".
He warned against sweeping laws that could give the state "enormous powers" to access knowledge and information about ordinary people's lives.
"We need to understand that it is in the nature of state power that decisions taken in the next few months and years about how the state may use these powers, and to what extent, are likely to be irreversible. They will be with us forever. And they will in turn will be built upon.
"So we should take very great care to imagine the world we are creating before we build it. We might end up living with something we can't bear."
Earlier this month, Home Secretary Jacqui Smith announced a consultation on new powers for the police and security service to store data on personal communications.
There are no plans for an enormous database which will contain the content of your emails, the texts that you send or the chats you have on the phone or online
The plans could lead to a massive database listing all mobile phone traffic, use of the internet and other technology - but not the actual content of the communication.
Critics have already dubbed the scheme as both Orwellian and unworkable - but Ms Smith said the alternative could be a "massive expansion of surveillance" to allow the police to keep pace with how criminals use technology to hide their plans.
Sir Ken did not refer to the proposals in his speech, but said the CPS had already played an important "rebalancing" role.
This included his public opposition to the now failed attempt to hold terrorism suspects for 42 days without charge.
"We have been absolutely right to resist, whenever they have been suggested, special courts, vetted judges and all the other paraphernalia of paranoia.
"Of course, you can have the Guantanamo model. You can have the model which says that we cannot afford to give people their rights, that rights are too expensive because of the nature of the threats we are facing.
"Or you can say, as I prefer to, that our rights are priceless. That the best way to face down those threats is to strengthen our institutions, rather than to degrade them.
"We would do well not to insult ourselves and all of our institutions and our processes of law in the face of these medieval delusions."
Sir Ken's successor as the director of public prosecutions is Keir Starmer QC. Mr Starmer is known for his human rights work and takes up the post on 1 November.
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