Surveillance involving trespass
Police do not have the power to place surveillance or interception devices on private property (without the consent of the occupier), unless this is to obtain evidence in relation to an offence:
- that is punishable by a prison term of at least seven years, or
- that is a specific offence under the Arms Act 1983, mainly offences relating to the unlawful possession of specific weapons.
Surveillance powers which don’t require a warrant
Police do not need a warrant to record (secretly or otherwise), if the police are:
- lawfully on private property and recording what they observe
- recording audio material of a voluntary conversation, so long as one person who is part of the conversation consents to this (if the police officer is a part of the conversation they can be the person who consents).
Police also have the power to conduct surveillance without a warrant in urgent or emergency situations that might otherwise require a warrant, see “Surveillance powers that require a warrant” below.
Surveillance powers that require a warrant
Police require a warrant issued by a judge to carry out the following surveillance activities:
- using an interception device to intercept private communication
- using a tracking device (unless it is solely to learn if something is opened or tampered with, and installing the device does not involve trespass)
- observing private activity and recording it by visual surveillance
- using a surveillance device that involves trespass
- observing and recording a private premises, even if it does not involve trespass, unless the surveillance is for:
- less than three hours in any 24-hour period, or
- less than eight hours in total.
Police powers to keep surveillance data
If criminal proceedings are commenced, raw surveillance data (including visual footage, audio recordings, etc) can be kept by the police until:
- the criminal proceedings related to the offence for which the surveillance was collected (including appeals) have finished,
- any appeal period for those criminal proceedings has expired (whichever is latest).
If no criminal proceedings are commenced, the police can keep raw surveillance data for:
- three years, if the data is required for an ongoing investigation, or
- up to two more years if specified by order (whichever is latest).