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Police forces across the United Kingdom successfully lobbied to use a face scanning system acknowledged as discriminatory against females, youths, and members of minority ethnic backgrounds, following complaints that a less biased version generated fewer potential suspects.

The Technology in Practice

UK forces utilize the national police database to carry out searches using historical face recognition. This process involves comparing a reference photograph of a suspect against a database of over 19 million custody photos to find possible hits.

Acknowledged Discrimination

The UK interior ministry conceded last week that the system was biased. This acknowledgment came after a review by the National Physical Laboratory (NPL) found it misidentified people of Black and Asian heritage and females at much greater frequency than Caucasian males. The Home Office stated it “had acted on the findings”.

“It prompts the issue of whether facial recognition only becomes effective if users accept biases in race and sex. Convenience is a poor argument for overriding basic freedoms.”

Known Issue

Internal documents show that this bias has been known about for over twelve months. Furthermore, law enforcement lobbied to reverse an earlier ruling that was designed to mitigate the problem.

Senior officers were informed of the system's bias in late 2024. The government-ordered laboratory study concluded the system was more likely to suggest false positives for images depicting females, Black people, and those under 40 years old.

A Policy U-Turn

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

However, this directive was reversed the following month following complaints from police that the modified technology was generating fewer “useful lines of inquiry”. Internal records show the higher threshold cut the proportion of queries that yielded potential matches from over half to a mere under 15%.

Severe Disparities

Although the Home Office and NPCC declined to specify what setting is now in operation, the latest independent review 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 Home Office commented on these findings: “Our evaluation identified that in a limited set of circumstances the algorithm is has a greater tendency to incorrectly include some demographic groups in its search results.”

Operational Effectiveness vs. Bias

Outlining the impact of the temporary raise to the system's accuracy setting, the police records state: “The change significantly reduces the effect of discrimination across legally safeguarded attributes of race, generation and gender but had a substantially detrimental effect on operational effectiveness”. The papers add that police units argued that “a once effective tactic now delivered results of questionable value”.

Wider Implementation Proposals

Meanwhile, the government has launched a two-and-a-half-month public review on its proposals to expand the use of facial recognition technology. Policing minister the relevant minister has labeled the technology as the “most significant advance since DNA matching”.

Criticism from Advisors and Monitors

Abimbola Johnson, head of the independent scrutiny and oversight board for the police race action plan, commented: “We observed scant discussion in race action plan meetings of the facial recognition rollout even with clear relevance with the strategy's goals.

“These revelations demonstrate once again that the anti-racism commitments the police has made via the race action plan are not being translated into broader operations. Our reports have cautioned that innovative tools are being implemented in a context where ethnic inequalities, weak scrutiny and poor data collection continue to exist.

“All deployment of facial recognition must meet rigorous official guidelines, be independently scrutinised, and prove it diminishes rather than compounds racial disparity.”

Home Office Response

A Home Office spokesperson stated: “We takes the conclusions of the report with utmost gravity and we have implemented changes. A updated software has been independently tested and acquired, which has demonstrated no measurable discrimination. It will be trialled in the coming months and will be undergo evaluation.

“Our priority is protecting the public. This revolutionary tool will assist police to apprehend and prosecute offenders. There is officer review in each stage of the procedure and no arrest or charge would be taken without specialist personnel carefully reviewing the results.”