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Police forces across the United Kingdom successfully lobbied to deploy a facial recognition system known to be discriminatory against females, young people, and members of ethnic minority groups, following complaints that a more accurate version generated fewer investigative leads.

The Technology in Practice

UK forces utilize the police national database (PND) to carry out searches using historical face recognition. This procedure entails matching a “probe image” of a suspect against a repository of over 19 million mugshots to find potential matches.

Acknowledged Discrimination

The UK interior ministry conceded last week that the technology was biased. This admission came after a review by the government's National Physical Laboratory determined it misidentified Black and Asian people and women at significantly higher rates than Caucasian males. The ministry said it “took steps on the findings”.

“It prompts the question of whether this technology only becomes effective if users tolerate discrimination in race and gender. Operational ease is a weak argument for overriding basic freedoms.”

Known Issue

Official papers show that this discriminatory flaw has been known about for over twelve months. Furthermore, law enforcement lobbied to reverse an earlier ruling that was designed to address the problem.

Senior officers were notified of the algorithmic discrimination in late 2024. The Home Office-commissioned laboratory study concluded the system was more likely to suggest incorrect matches for photos of females, Black people, and those under 40 years old.

A Reversed Decision

In reaction, the national police leadership body ordered that the accuracy setting required for possible hits be raised 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 producing fewer “investigative leads”. Internal records indicate the higher threshold reduced the proportion of searches that yielded potential matches from over half to a just 14%.

Severe Disparities

Although the Home Office and NPCC refused to say what setting is now in operation, the recent independent review discovered the system could produce false positives for Black women almost 100 times more frequently than for Caucasian women at certain settings.

The Home Office commented on these findings: “Our evaluation identified that in a limited set of circumstances the algorithm is more likely to wrongly flag some demographic groups in its match reports.”

Balancing Utility and Fairness

Describing the impact of the brief increase to the system's confidence threshold, the police records note: “The change significantly reduces the impact of discrimination across protected characteristics of race, generation and gender but had a significant negative impact on operational effectiveness”. The documents add that police units complained that “a previously useful tool now delivered outcomes of questionable value”.

Broader Rollout Plans

Meanwhile, the UK administration has opened a ten-week consultation on its plans to expand the use of facial recognition technology. Policing minister Sarah Jones has labeled the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the national policing equality strategy, said: “We observed scant discussion through equality strategy sessions of the technology deployment even with obvious cross-over with the plan’s concerns.

“These revelations demonstrate yet again that the pledges to combat discrimination the police has made via the equality initiative are not being translated into broader operations. Independent assessments have cautioned that new technologies are being implemented in a landscape where ethnic inequalities, inadequate oversight and poor data collection continue to exist.

“All deployment of facial recognition must meet strict national standards, be independently scrutinised, and demonstrate it diminishes rather than exacerbates racial disparity.”

Home Office Response

A Home Office spokesperson stated: “We treat the findings of the report 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 subject to further assessment.

“Our priority is protecting the public. This gamechanging technology will assist police to apprehend and prosecute offenders. There is human involvement in every step of the process and no further action would be taken without trained officers carefully reviewing the results.”