Interception of communications

What is interception of communications?

The interception of communications includes listening to someone’s phone calls or opening and reading their messages. This is only allowed where a Secretary of State (usually the Home Secretary) is satisfied it is necessary and proportionate and has issued a warrant authorising the activity, which must in turn be approved by a an independent judge. 

The warrants are issued under the Investigatory Powers Act, and in acting on them we must comply with the Interception of Communications Code of Practice. 

MI5 can also request communications data under the Investigatory Powers Act. As with interception, MI5 must show that this is necessary and proportionate. Our acquisition and use of intercepted communications and communications data is overseen by the Investigatory Powers Commissioner’s Office.