Facial Recognition Technology
What is facial recognition technology?
Facial recognition is a technology capable of comparing a human face from a digital image against a database of faces.
We use facial recognition technology to prevent and detect crime and help protect vulnerable people.
Whenever we use facial recognition technology, we recognise there is an ongoing need to balance privacy and protection concerns, in addition to considering its legal and ethical implications.
How does facial recognition technology work?
It analyses key facial features and generates a mathematical representation of these features. It then compares them against the mathematical representation of known faces in a database, generating possible matches.
At Gwent Police we use this in two ways:
- Retrospective facial recognition (RFR) compares still images of faces of unknown subjects against a reference image database in order to identify them after an event.
- Operator initiated facial recognition (OIFR) is a mobile phone use of the technology, which compares a photograph of a person’s face taken on a mobile phone to the predetermined watchlist to assist an officer to identify a subject.
Images are typically supplied from CCTV, mobile phone footage or social media. These images are then compared against our custody images.
The reference database that we use are custody images from South Wales and Gwent Police. These contain in excess of 600,000 images.
After a search is made, the technology reorders the reference image database from the most likely to the least likely possible match.
An operator will typically review the top 200 possible matches to decide whether a match has been made. If the operator determines a match has been made, they will inform the investigating officer. The investigating officer will review the match and add the person to the investigation as a suspect.
What is the operator initiated facial recognition (OIFR)?
FRApp enables our officers to use the facial recognition technology on their mobile phones. It compares a photograph of a person’s face taken on a mobile phone with facial images contained in a predetermined watchlist(s) in order to assist an officer to identify a subject. These images will come from our custody images and those of South Wales Police, as well as our missing persons list.
We will always explain to the person when we use the OIFR app and let them know how they can contact us to ask further questions.
People who are not included on a watchlist cannot be identified. The image, captured on the mobile device, and biometric data are automatically and immediately deleted after a search is carried out.
When is the OIFR app used?
The OIFR app is used as an ‘on-street’ intelligence tool to help officers in identifying an unknown person, and when there are reasonable grounds for its use.
These may include someone unable to provide their details because they are, unconscious, have mental health or communication barriers, are incapable due to drink or drugs or are deceased. It may also be used if someone refuses to provide their details or is reasonably suspected of providing false details.
However, one of the following must also apply:
- The person is deceased
- Reported as a missing person
- Suspected that they have committed an offence, wanted by the courts, subject to bail conditions or a court order.
- Presenting a risk of harm to themselves or others
The OIFR app will not be used to replace traditional means of identification where officers will talk with someone to gather their name and any proof of identity. However, sometimes this is not possible and the app provides an alternative means of identifying the person.