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Law enforcement agencies across the United Kingdom effectively campaigned to use a facial recognition system known to be discriminatory against females, youths, and members of minority ethnic backgrounds, following complaints that a less biased version produced a reduced number of potential suspects.

The Technology in Practice

British police utilize the national police database to conduct searches using historical face recognition. This process entails comparing a “probe image” of a person of interest against a database of more than 19 million mugshots to find potential matches.

Admitted Bias

The Home Office conceded last week that the technology was biased. This admission came after a review by the National Physical Laboratory (NPL) determined it misidentified Black and Asian people and females at significantly higher rates than white men. The Home Office stated it “took steps on the findings”.

“It prompts the issue of whether facial recognition only becomes effective if users tolerate biases in race and gender. Operational ease is a poor argument for disregarding basic freedoms.”

Long-Standing Problem

Internal documents show that this discriminatory flaw has been recognized for more than a year. Furthermore, police forces argued to overturn an earlier ruling that was intended to address the problem.

Senior officers were notified of the system's bias in September 2024. The Home Office-commissioned NPL review found the system was had a higher probability to produce false positives for photos of women, Black people, and those aged 40 and under.

A Policy U-Turn

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

However, this directive was overturned the next month following complaints from police that the modified technology was generating a lower number of “investigative leads”. NPCC documents show the higher threshold reduced the number of queries that yielded possible identifications from 56% to a just under 15%.

Severe Disparities

Although the authorities declined to specify what threshold is now in operation, the recent NPL study discovered the system could produce false positives for women of Black heritage almost 100 times more often than for white women at specific configurations.

The Home Office commented on these results: “The testing found that in a specific scenarios the algorithm is has a greater tendency to incorrectly include some demographic groups in its search results.”

Balancing Utility and Fairness

Outlining the effect of the temporary raise to the system's accuracy setting, the police records state: “This adjustment significantly reduces the effect of bias across legally safeguarded attributes of ethnicity, age and gender but had a substantially detrimental effect on police efficiency”. The documents further note that police units argued that “a previously useful tool now delivered outcomes of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has launched a two-and-a-half-month public review on its plans to expand the use of biometric scanning systems. The minister for police Sarah Jones has labeled the technology as the “biggest breakthrough since genetic fingerprinting”.

Expert and Oversight Concerns

The chair of a police oversight board, head of the independent scrutiny and oversight board for the national policing equality strategy, commented: “There was very little consideration in race action plan meetings of the facial recognition rollout even with obvious cross-over with the plan’s concerns.

“These revelations demonstrate once again that the anti-racism commitments the police has undertaken via the equality initiative are failing to be integrated into broader operations. Our reports have cautioned that new technologies are being implemented in a landscape where ethnic inequalities, weak scrutiny and poor data collection already persist.

“Any use of facial recognition must meet rigorous official guidelines, be subject to external review, and prove it diminishes rather than compounds ethnic bias.”

Official Statement

A Home Office spokesperson stated: “We treat the conclusions of the study with utmost gravity and we have already taken action. A updated software has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be undergo further assessment.

“Our priority is protecting the public. This gamechanging technology will support officers to apprehend and prosecute offenders. There is officer review in each stage of the process and no arrest or charge would be taken without trained officers carefully reviewing the output.”