Police use of live facial recognition technology: Challenges and concerns

Last week was a landmark moment in the police use of ‘Live Facial Recognition’ (LFR) technology.

An independent report, published by Essex University, found it is “highly possible” that the use of LFR by the Metropolitan Police “would be held unlawful if challenged before the courts.”

The report found the Met had provided inadequate information to the public about the technology and that more needs to be done to ensure human rights are properly considered every time it is used.

But what is LFR? How are the police using it and what needs to be done to ensure the technology is deployed legally and effectively? This Insight provides an overview of police use of LFR in the UK.

What is LFR technology?

If you have ever used an e-passport gate or unlocked your smartphone by looking at it, you have used facial recognition technology. Facial recognition technology studies two images of faces and determines whether they match.

Live Facial Recognition is slightly different because, unlike at the e-passport gate, the images LFR programmes are attempting to match have been taken in uncontrolled environments. Police forces use cameras to take live images of crowds of people at public events and spaces. These images are then analysed by computers against police watchlists to identify wanted individuals. Police staff should verify the matches to ensure they are accurate before engaging with suspects.

When has the police used LFR?

Two police forces have been pioneering the use of LFR in the UK. The Metropolitan Police conducted ten trials of the technology between 2016 and 2018 and South Wales Police has been using the technology since May 2017. They have deployed the technology at music concerts, major sporting events, at Notting Hill Carnival, on high streets and in shopping centres.

LFR has aided the arrest of a number of suspects. 14 people were arrested in South Wales between May 2017 and May 2018 after being matched during an LFR trial. The Met has also made a number of arrests whilst trialling the technology in the capital.

Both police forces have had their use of LFR independently reviewed by nearby universities. When Cardiff University published its report on the use of LFR is South Wales in September 2018, it concluded that “some of the results delivered by the technology were impressive.” However, it found: “the effort and investment required to get LFR to regularly contribute to delivering tangible policing outcomes was probably more than was anticipated.” Essex University was more critical of the Met’s use of LFR. It found it was “highly possible” the Met’s use of the technology would be found unlawful.

What are the concerns over LFR?

Several groups have raised concerns over the use of LFR by the police.

The London Assembly Oversight Committee has asked the Mayor of London to suspend the Met’s use of LFR until “a proper legal framework was in place”. The London Policing Ethics Panel has called for five conditions to be introduced before the Met use the technology. The Law Society has argued that there needs to be much stronger regulation on all use of predictive technologies in the criminal justice system (including LFR).

Concerns about LFR centre around three key areas:

1.The technology is not good enough. The computer programs generate a high number of false matches. Studies show there is a racial and gender bias in the way the computer generates matches. The faces of black and Asian people, and women, are more likely to be incorrectly matched with watchlist individuals.

2. The legal and oversight framework is too weak. There is currently no specific piece of legislation that grants police the power to use LFR. Instead, the police rely on common law powers to use the technology and must show they are compliant with human rights, data protection and freedom of information legislation when they do so. Some argue that the current oversight of LFR is too fragmented and relies too heavily on the police self-regulating.

3. LFR disproportionately encroaches on the right to privacy. The technology scans the faces of all people in the public space it is being used. Therefore, some argue it is not targeted enough and allows the police to gather biometric data on innocent members of the public.

These arguments are being tested in the courts. The human rights campaign group Liberty is assisting Kevin Bridges – a man who was scanned by LFR by South Wales Police – to take a case against the force to the High Court in Cardiff. Liberty and Mr Bridges argue the use of LFR contravenes the European Convention of Human Rights and breaches data protection legislation.

A core strand of Liberty’s argument is that there is an inadequate legal basis, oversight and policy to govern LFR and that it is inherently discriminatory because it disproportionately matches black and Asian people, and women. The High Court in Cardiff began hearing the case in May 2019. Its outcome will have a profound impact on the future use of this technology by the police.  

How has the police and Government responded?

The Government and the police have both argued that the current legal framework for the use of LFR is sufficient. The Metropolitan Police has published a Legal Mandate for its use of LFR. It sets out how the Met thinks its use of LFR is compliant with human rights, data protection and freedom of information legislation. Minister for Policing in the Home Office, Nick Hurd cited much of the same legislation in a speech he gave to the House of Commons earlier this year.

However, the Government has indicated that some reform of the governance of LFR is likely. Its Biometrics Strategy, published last summer, committed to:

“Establish a new oversight and advisory board to coordinate consideration of issues relating to law enforcement’s use of facial images and facial recognition systems.”

The Government has also indicated it is “reviewing options to simplify and extend current governance and oversight arrangements for biometrics.”

What next for LFR?

The High Court case in Cardiff will provide another landmark moment for the governance of police use of LFR. The judgement will doubtless prompt policy makers to think hard about how to regulate policing by camera.

Further reading


About the author: Jenny Brown is a researcher at the House of Commons Library, specialising in home affairs and justice.


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Image: South Wales Police