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Law enforcement agencies across the UK successfully lobbied to use a face scanning system known to be discriminatory against females, young people, and members of minority ethnic backgrounds, following complaints that a more accurate version generated a reduced number of potential suspects.

How the System Works

UK forces use the national police database to conduct searches using historical face recognition. This procedure involves 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 conceded last week that the technology was flawed. This admission came after a review by the National Physical Laboratory (NPL) found it incorrectly matched people of Black and Asian heritage and women at significantly higher rates than Caucasian males. The Home Office stated it “had acted on the findings”.

“It prompts the issue of whether facial recognition only becomes useful if users accept discrimination in ethnicity and sex. Convenience is a poor argument for disregarding basic freedoms.”

Long-Standing Problem

Official papers reveal that this discriminatory flaw has been known about for more than a year. Furthermore, police forces argued to overturn an initial decision that was designed to mitigate the problem.

Senior officers were informed of the system's bias in late 2024. The government-ordered NPL review found the system was had a higher probability to produce false positives for images depicting females, Black people, and those under 40 years old.

A Reversed Decision

In response, the National Police Chiefs’ Council (NPCC) mandated that the accuracy setting required for possible hits be increased to a level where the bias was greatly diminished.

However, this directive was reversed the next month following complaints from police that the adjusted system was producing a lower number of “investigative leads”. NPCC documents indicate the stricter setting reduced the proportion of searches resulting in possible identifications from 56% to a just under 15%.

Severe Disparities

Although the Home Office and NPCC refused to say what setting is now in operation, the latest independent review found the system could produce incorrect matches for women of Black heritage almost 100 times more often than for Caucasian women at certain settings.

The Home Office commented on these results: “The testing identified that in a limited set of circumstances the software is more likely to wrongly flag some population segments in its search results.”

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 legally safeguarded attributes of ethnicity, age and sex but had a substantially detrimental effect on police efficiency”. The documents add that forces complained that “a once effective tactic now delivered results of limited benefit”.

Broader Rollout Plans

Meanwhile, the government has launched a two-and-a-half-month public review on its proposals to widen the use of facial recognition technology. 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, chair of the independent scrutiny and oversight board for the national policing equality strategy, commented: “There was very little consideration through race action plan meetings of the technology deployment despite clear relevance with the plan’s concerns.

“This disclosure show yet again that the anti-racism commitments policing has made via the equality initiative are failing to be integrated into wider practice. Independent assessments have warned that new technologies are being rolled out in a context where racial disparities, inadequate oversight and faulty information gathering already persist.

“Any use of this technology must adhere to rigorous official guidelines, be independently scrutinised, and demonstrate it reduces rather than compounds racial disparity.”

Official Statement

A government representative stated: “The Home Office treat the findings of the study with utmost gravity and we have implemented changes. A new algorithm has been independently tested and acquired, which has no statistically significant bias. It will be trialled early next year and will be subject to further assessment.

“The foremost aim is protecting the public. This gamechanging technology will assist officers to put criminals and rapists behind bars. There is officer review in each stage of the procedure and no further action would be pursued without trained officers meticulously examining the results.”