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Police forces across the UK effectively campaigned to deploy a facial recognition system acknowledged as discriminatory against females, youths, and individuals from minority ethnic backgrounds, after complaining that a less biased version generated a reduced number of potential suspects.

The Technology in Practice

British police use the national police database to carry out searches using historical face recognition. This procedure entails matching a “probe image” of a suspect against a database of over 19 million custody photos to identify possible hits.

Admitted Bias

The Home Office admitted last week that the system was flawed. This admission followed a study by the government's National Physical Laboratory found it incorrectly matched Black and Asian people and females at significantly higher rates than Caucasian males. The ministry stated it “had acted on the findings”.

“It prompts the issue of whether facial recognition only becomes useful if users accept biases in race 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, police forces lobbied to reverse an initial decision that was intended to address the problem.

Police bosses were notified of the algorithmic discrimination in late 2024. The Home Office-commissioned NPL review concluded 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 response, the National Police Chiefs’ Council (NPCC) mandated that the confidence threshold required for potential matches be raised to a point where the bias was greatly diminished.

However, this directive was overturned the following month after forces complained that the modified technology was producing a lower number of “investigative leads”. NPCC documents show the stricter setting cut the number of queries resulting in potential matches from over half to a mere 14%.

Profound Inequalities

Although the Home Office and NPCC declined to specify what threshold is now in operation, the latest NPL study discovered the system could generate incorrect matches for women of Black heritage almost 100 times more often than for white women at specific configurations.

The ministry stated on these findings: “Our evaluation identified that in a specific scenarios the algorithm is has a greater tendency to wrongly flag some demographic groups in its match reports.”

Balancing Utility and Fairness

Outlining the impact of the temporary raise to the system's accuracy setting, the police records state: “This adjustment significantly reduces the impact of bias across protected characteristics of ethnicity, age and gender but had a substantially detrimental effect on operational effectiveness”. The papers add that police units complained that “a once effective tactic now delivered outcomes of questionable value”.

Broader Rollout Plans

Meanwhile, the government has launched a two-and-a-half-month consultation on its plans to widen the use of facial recognition technology. The minister for police Sarah Jones has described the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

The chair of a police oversight board, chair of the advisory panel 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.

“This disclosure show yet again that the pledges to combat discrimination policing has made through the equality initiative are failing to be integrated into wider practice. Our reports have warned that new technologies are being rolled out in a landscape where ethnic inequalities, weak scrutiny and faulty information gathering continue to exist.

“Any use of facial recognition must adhere to strict national standards, be independently scrutinised, and prove it reduces rather than compounds racial disparity.”

Official Statement

A government representative said: “The Home Office takes the conclusions of the report seriously and we have implemented changes. A updated software has been externally evaluated and procured, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be subject to further assessment.

“Our priority is ensuring public safety. This gamechanging technology will assist police to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no further action would be taken without trained officers meticulously examining the results.”