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

How the System Works

British police utilize the national police database to carry out retrospective facial recognition searches. This procedure entails comparing a “probe image” of a suspect against a repository of over 19 million custody photos to identify possible hits.

Acknowledged Discrimination

The Home Office conceded last week that the technology was flawed. This admission followed a review by the National Physical Laboratory (NPL) found it misidentified people of Black and Asian heritage and women at much greater frequency than Caucasian males. The ministry stated it “took steps on the findings”.

“It prompts the issue of whether this technology only becomes effective if users tolerate discrimination in race and sex. Convenience is a poor argument for disregarding fundamental rights.”

Known Issue

Internal documents show that this discriminatory flaw has been recognized for more than a year. Furthermore, law enforcement lobbied to reverse an initial decision that was intended to address the problem.

Police bosses were informed of the algorithmic discrimination in September 2024. The Home Office-commissioned laboratory study concluded the system was more likely to produce incorrect matches for images depicting females, individuals of Black ethnicity, and those under 40 years old.

A Policy U-Turn

In reaction, the national police leadership body mandated that the confidence threshold required for potential matches be increased to a point where the disparity was significantly reduced.

However, this decision was overturned the following month after forces complained that the adjusted system was generating a lower number of “useful lines of inquiry”. NPCC documents show the higher threshold reduced the proportion of searches that yielded possible identifications from over half to a just 14%.

Profound Inequalities

Although the authorities refused to say what setting is now in operation, the latest independent review discovered the system could generate false positives for women of Black heritage almost 100 times more often than for Caucasian women at specific configurations.

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

Operational Effectiveness vs. Bias

Describing the impact of the temporary raise to the system's confidence threshold, the police records note: “This adjustment significantly reduces the impact of discrimination across legally safeguarded attributes of race, age and gender but had a substantially detrimental effect on operational effectiveness”. The papers further note that forces complained that “a previously useful tool now delivered results of questionable value”.

Wider Implementation Proposals

Meanwhile, the UK administration has launched a two-and-a-half-month public review on its proposals to expand the use of facial recognition technology. The minister for police the relevant minister has described the technology as the “most significant advance since genetic fingerprinting”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the advisory panel for the national policing equality strategy, commented: “We observed very little consideration in equality strategy sessions of the facial recognition rollout despite clear relevance with the strategy's goals.

“This disclosure demonstrate once again that the pledges to combat discrimination the police has made through the race action plan are failing to be integrated into wider practice. Independent assessments have cautioned that innovative tools are being rolled out in a context where ethnic inequalities, weak scrutiny and faulty information gathering already persist.

“Any use of this technology must adhere to rigorous official guidelines, be subject to external review, and prove it diminishes rather than exacerbates racial disparity.”

Official Statement

A government representative said: “We takes the conclusions of the report with utmost gravity and we have implemented changes. A updated software has been externally evaluated and procured, which has no statistically significant bias. It will be trialled early next year and will be undergo evaluation.

“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 process and no arrest or charge would be taken without trained officers carefully reviewing the output.”