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Police forces across the UK effectively campaigned to deploy a face scanning system known to be discriminatory against women, young people, and members of ethnic minority groups, following complaints that a less biased version generated a reduced number of investigative leads.

The Technology in Practice

UK forces utilize the national police database to carry out searches using historical face recognition. This procedure entails matching a “probe image” of a person of interest against a database of more than 19 million custody photos to identify potential matches.

Acknowledged Discrimination

The UK interior ministry admitted last week that the technology was flawed. This acknowledgment followed a study by the government's National Physical Laboratory determined it misidentified people of Black and Asian heritage and women at much greater frequency than Caucasian males. The ministry said it “had acted on the findings”.

“It prompts the question of whether this technology only becomes useful if users accept discrimination in race and sex. Convenience is a poor argument for disregarding fundamental rights.”

Long-Standing Problem

Internal documents reveal that this discriminatory flaw has been known about for more than a year. Furthermore, law enforcement argued to overturn an earlier ruling that was designed to mitigate the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The government-ordered laboratory study found the system was had a higher probability to suggest incorrect matches for photos of females, individuals of Black ethnicity, and those aged 40 and under.

A Reversed Decision

In reaction, the National Police Chiefs’ Council (NPCC) mandated that the confidence threshold required for possible hits be increased to a level where the bias was greatly diminished.

However, this decision was overturned the next month following complaints from police that the modified technology was producing fewer “useful lines of inquiry”. Internal records indicate the stricter setting cut the number of queries resulting in possible identifications from over half to a mere under 15%.

Severe Disparities

Although the Home Office and NPCC refused to say what threshold is now in operation, the latest independent review discovered the system could generate incorrect matches for women of Black heritage almost 100 times more frequently than for white women at certain settings.

The Home Office stated on these results: “Our evaluation identified that in a limited set of circumstances the algorithm is more likely to incorrectly include some demographic groups in its match reports.”

Operational Effectiveness vs. Bias

Describing the impact of the brief increase to the system's accuracy setting, the police records note: “This adjustment greatly lessens the effect of bias across protected characteristics of ethnicity, age and gender but had a significant negative impact on police efficiency”. The papers further note that police units complained that “a previously useful tool now delivered results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the UK administration has launched a ten-week public review on its proposals to expand the use of biometric scanning systems. Policing minister Sarah Jones has described the tool as the “biggest breakthrough since DNA matching”.

Criticism from Advisors and Monitors

The chair of a police oversight board, head of the advisory panel for the national policing equality strategy, said: “There was scant consideration in race action plan meetings of the facial recognition rollout even with clear relevance with the strategy's goals.

“This disclosure show yet again that the anti-racism commitments the police has undertaken through the race action plan are failing to be integrated into broader operations. Our reports have cautioned that new technologies are being rolled out in a context where racial disparities, weak scrutiny and faulty information gathering continue to exist.

“All deployment of facial recognition must adhere to strict national standards, be independently scrutinised, and demonstrate it diminishes rather than compounds ethnic bias.”

Official Statement

A government representative stated: “We takes the findings of the study with utmost gravity and we have already taken action. A new algorithm has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be undergo further assessment.

“Our priority is protecting the public. This revolutionary tool will assist officers to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no further action would be pursued without trained officers carefully reviewing the output.”