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Law enforcement agencies across the UK effectively campaigned to deploy a facial recognition system known to be biased against females, youths, and individuals from ethnic minority groups, following complaints that a more accurate version generated a reduced number of investigative leads.

The Technology in Practice

British police utilize the police national database (PND) to carry out retrospective facial recognition searches. This procedure entails matching a reference photograph of a suspect against a database of over 19 million custody photos to identify potential matches.

Acknowledged Discrimination

The Home Office conceded last week that the system was biased. This admission followed a review by the government's National Physical Laboratory determined it misidentified people of Black and Asian heritage and females at much greater frequency than white men. The Home Office said it “had acted on the findings”.

“This raises the question of whether this technology only becomes effective if users accept discrimination in ethnicity and gender. Operational ease is a poor argument for disregarding fundamental rights.”

Long-Standing Problem

Official papers reveal that this discriminatory flaw has been known about for over twelve months. Furthermore, law enforcement lobbied to reverse an initial decision that was designed to mitigate the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The Home Office-commissioned laboratory study found the system was more likely to produce false positives for photos of females, individuals of Black ethnicity, and those under 40 years old.

A Reversed Decision

In reaction, the national police leadership body ordered that the accuracy setting required for potential matches be increased to a level where the bias was greatly diminished.

However, this directive was overturned the next month following complaints from police that the adjusted system was generating fewer “investigative leads”. Internal records show the higher threshold reduced the number of queries that yielded potential matches from 56% to a mere under 15%.

Severe Disparities

Although the authorities refused to say what threshold is now in operation, the latest independent review discovered the system could produce incorrect matches for women of Black heritage almost 100 times more frequently than for Caucasian women at certain settings.

The ministry stated on these results: “Our evaluation identified that in a specific scenarios the software is has a greater tendency to incorrectly include some population segments in its match reports.”

Balancing Utility and Fairness

Outlining the effect of the brief increase to the system's accuracy setting, the NPCC documents note: “This adjustment greatly lessens the effect of discrimination across protected characteristics of race, age and sex but had a significant negative impact on operational effectiveness”. The papers further note that police units complained that “a once effective tactic returned results of limited benefit”.

Broader Rollout Plans

Meanwhile, the UK administration has opened a ten-week public review on its proposals to widen the use of biometric scanning systems. The minister for police the relevant minister has labeled the technology as the “biggest breakthrough since genetic fingerprinting”.

Criticism from Advisors and Monitors

The chair of a police oversight board, head of the advisory panel for the police race action plan, commented: “There was very little consideration through race action plan meetings of the facial recognition rollout despite clear relevance with the plan’s concerns.

“This disclosure demonstrate once again that the anti-racism commitments policing has made through the equality initiative are not being translated into wider practice. Our reports have warned that new technologies are being rolled out in a landscape where racial disparities, weak scrutiny and poor data collection continue to exist.

“Any use of facial recognition must adhere to strict national standards, be subject to external review, and demonstrate it reduces rather than compounds ethnic bias.”

Home Office Response

A government representative stated: “The Home Office takes the conclusions of the study with utmost gravity and we have implemented changes. A updated software has been independently tested and acquired, which has no statistically significant bias. It will be tested early next year and will be undergo further assessment.

“Our priority is protecting the public. This revolutionary tool will support police to put criminals and rapists behind bars. There is officer review in each stage of the procedure and no further action would be taken without trained officers meticulously examining the results.”