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Police forces across the United Kingdom successfully lobbied to deploy a facial recognition system known to be discriminatory against women, youths, and individuals from ethnic minority groups, following complaints that a more accurate version produced a reduced number of potential suspects.

How the System Works

UK forces utilize the national police database to carry out searches using historical face recognition. This process entails matching a “probe image” of a suspect against a database of over 19 million custody photos to find possible hits.

Acknowledged Discrimination

The Home Office admitted last week that the technology was flawed. This admission followed a study by the National Physical Laboratory (NPL) determined it misidentified Black and Asian people and females at much greater frequency than white men. The ministry stated it “took steps on the findings”.

“This raises the issue of whether this technology only becomes useful if users tolerate discrimination in ethnicity and gender. Operational ease is a weak argument for overriding fundamental rights.”

Long-Standing Problem

Official papers reveal that this discriminatory flaw has been known about for more than a year. Furthermore, law enforcement lobbied to reverse an initial decision that was intended to mitigate the problem.

Police bosses were informed of the system's bias in late 2024. The Home Office-commissioned NPL review found the system was more likely to produce incorrect matches for images depicting females, 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 level where the disparity was greatly diminished.

However, this directive was overturned the next month after forces complained that the adjusted system was producing fewer “useful lines of inquiry”. NPCC documents show the higher threshold cut the number of queries that yielded possible identifications from over half to a mere 14%.

Severe Disparities

Although the authorities declined to specify what threshold is now in operation, the latest independent review found the system could generate false positives for Black women almost 100 times more often than for Caucasian women at certain settings.

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

Operational Effectiveness vs. Bias

Outlining the impact of the brief increase to the system's confidence threshold, the police records note: “This adjustment greatly lessens the effect of bias 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 returned results of limited benefit”.

Wider Implementation Proposals

Meanwhile, the UK administration has launched a two-and-a-half-month consultation on its plans to widen the use of biometric scanning systems. The minister for police Sarah Jones has described the technology as the “most significant advance since DNA matching”.

Expert and Oversight Concerns

The chair of a police oversight board, head of the advisory panel for the national policing equality strategy, commented: “There was very little discussion through equality strategy sessions of the facial recognition rollout despite obvious cross-over with the strategy's goals.

“These revelations show once again that the pledges to combat discrimination policing has made via the race action plan are not being translated into wider practice. 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 this technology must meet strict national standards, be subject to external review, and prove it reduces rather than compounds racial disparity.”

Official Statement

A government representative said: “We takes the findings of the report seriously and we have implemented changes. A new algorithm has been externally evaluated and acquired, which has demonstrated no measurable discrimination. It will be tested early next year and will be undergo evaluation.

“Our priority is protecting the public. This gamechanging technology will assist police to put criminals and rapists behind bars. There is human involvement in each stage of the procedure and no arrest or charge would be taken without trained officers meticulously examining the results.”