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Law enforcement agencies across the UK successfully lobbied to use a facial recognition system acknowledged as discriminatory against females, youths, and individuals from ethnic minority groups, following complaints that a less biased version produced a reduced number of investigative leads.

The Technology in Practice

British police utilize the national police database to conduct searches using historical face recognition. This procedure entails matching a reference photograph of a person of interest against a repository of more than 19 million custody photos to identify potential matches.

Acknowledged Discrimination

The UK interior ministry admitted last week that the system was flawed. This acknowledgment followed a review by the government's National Physical Laboratory determined it incorrectly matched people of Black and Asian heritage and women at significantly higher rates than white men. The ministry stated it “had acted on the findings”.

“This raises the question of whether this technology only becomes useful if users accept biases in race and gender. Convenience is a weak argument for disregarding basic freedoms.”

Known Issue

Official papers show that this discriminatory flaw has been recognized for over twelve months. Furthermore, law enforcement argued to overturn an initial decision that was intended to mitigate the problem.

Police bosses were notified of the algorithmic discrimination in September 2024. The Home Office-commissioned NPL review concluded the system was more likely to suggest false positives for images depicting women, individuals of Black ethnicity, and those under 40 years old.

A Policy U-Turn

In reaction, the National Police Chiefs’ Council (NPCC) ordered that the accuracy setting required for potential matches be raised to a point where the bias was greatly diminished.

However, this directive was overturned the next month after forces complained that the adjusted system was producing fewer “investigative leads”. NPCC documents indicate the stricter setting cut the proportion of queries that yielded potential matches from 56% to a mere 14%.

Profound Inequalities

Although the authorities declined to specify what threshold is now in operation, the latest NPL study found the system could generate false positives for women of Black heritage almost 100 times more frequently than for Caucasian women at specific configurations.

The ministry stated on these findings: “The testing found that in a specific scenarios the software is more likely to incorrectly include some population segments in its match reports.”

Operational Effectiveness vs. Bias

Describing the impact of the brief increase to the system's confidence threshold, the NPCC documents state: “The change significantly reduces the impact of discrimination across legally safeguarded attributes of race, age and sex but had a significant negative impact on operational effectiveness”. The papers further note that forces argued that “a previously useful tool now delivered results of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has opened a ten-week consultation on its plans to widen the use of facial recognition technology. The minister for police 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 police race action plan, said: “There was very little discussion through 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 pledges to combat discrimination policing has undertaken through the race action plan are not being translated into wider practice. Independent assessments have warned that new technologies are being implemented in a landscape where ethnic inequalities, weak scrutiny and faulty information gathering already persist.

“All deployment of facial recognition must adhere to strict national standards, be subject to external review, and prove it diminishes rather than exacerbates ethnic bias.”

Home Office Response

A Home Office spokesperson said: “We takes the conclusions of the study seriously and we have already taken action. A updated software has been independently tested and acquired, which has demonstrated no measurable discrimination. It will be tested in the coming months and will be undergo further assessment.

“The foremost aim is ensuring public safety. This gamechanging technology will assist officers to put criminals and rapists behind bars. There is human involvement in every step of the procedure and no further action would be pursued without trained officers meticulously examining the output.”