Use of intercepted information as evidence in legal proceedings

Reliance by the Crown Prosecution Service on intercepted material is a controversial subject. The position now, which is the same for the interception of telecommunications, is as follows. When intercepted under warrant, neither the fact that a communication has been intercepted, nor its content, may be revealed or used in any way, for the purpose of or in connection with legal proceedings. At present, interception warrants are intelligence gathering tools only. As for ‘communications data’, and information gathered where communications have been intercepted lawfully without the need or a warrant, for example under participant monitoring, the intercepted information can be used as evidence at trial. However, the judge will always the power to exclude such evidence if he considers that it was gathered oppressively, or if its prejudicial effect would outweigh its value in proving any material allegations.

Liberty has campaigned for the law to be reformed to allow the use of interpted communications in criminal trials, subject to appropriate safeguards, but the Government has rejected this, arguing that the use of intercepted material as evidence may expose the technology and methods by which crucial intelligence is gathered, which would give criminal elements a means to avoid interception in future, and would compromise important security operations undertaken for public protection.