London Daily

Focus on the big picture.
Sunday, Aug 31, 2025

Digital forensics experts prone to bias, study shows

Digital forensics experts prone to bias, study shows

Participants found more or less evidence on hard drive depending on what contextual information they had
Devices such as phones, laptops and flash drives are becoming increasingly central to police investigations, but the reliability of digital forensics experts’ evidence has been called into question.

A study found that experts tended to find more or less evidence on a suspect’s computer hard drive to implicate or exonerate them depending on the contextual information about the investigation that they were given.

Even those presented with the same information often reached different conclusions about the evidence.

Such biases are known to be a problem in other forensic disciplines including fingerprint analysis, but this is the first time it has been demonstrated in digital forensics.

“I cannot overemphasise the importance of forensic scientists understanding the potential for unintentional bias, and of ensuring they take measures to minimise the risks,” said Dr Gillian Tully, a professor of practice for forensic science policy and regulation at King’s College London and former UK forensic science regulator.

Digital evidence now features in around 90% of criminal cases. Digital examiners working in police and private laboratories use specialised software and other techniques to secure, retrieve and analyse data from suspects’ communications, photos and other digital interactions that could shed light on their activities.

However, the field’s rapid growth means that has not been subjected to the same scientific scrutiny as other forensic techniques. “It has been described as the wild west because it wasn’t developed systematically and scientifically before it went into the criminal justice system,” said Dr Itiel Dror, an expert in cognitive bias at University College London who carried out the study.

Ian Walden, a professor of information and communications law at Queen Mary, University of London, said there was a tendency to believe the machine. “This study shows that we need to be careful about electronic evidence,” Walden said. “Not only should we not always trust the machine, we can’t always trust the person that interprets the machine.”

Dror and Nina Sunde at the University of Oslo, Norway, gave 53 digital forensics examiners from eight countries including the UK the same computer hard drive to analyse. Some of the examiners were provided with only basic contextual information about the case, while others were told the suspect had confessed to the crime, had a strong motive for committing it or that the police believed she had been framed.

The study, soon to be published in Forensic Science International: Digital Investigation, found that the examiners who had been led to believe the suspect might be innocent documented the fewest traces of evidence in the files, while those who knew of a potential motive identified the most traces.

It also found low levels of consistency between examiners who were given the same contextual information, in terms of the observations, interpretations and conclusions they drew from the files.

“Digital forensics examiners need to acknowledge that there’s a problem and take measures to ensure they’re not exposed to irrelevant, biased information,” said Dror. “They also need to be transparent to the courts about the limitations and the weaknesses, acknowledging that different examiners may look into the same evidence and draw different conclusions.”

In her final report before stepping down as forensic science regulator earlier this year, Tully called for improved compliance with quality standards for digital forensic labs, many of which have not been accredited, and greater scrutiny of scientific evidence in court.

Dr David Gresty, a senior lecturer in computer forensics at the University of Greenwich, said: “We have every reason to believe that an expert acting in good faith, but through a mistake of interpretation, could easily mislead a courtroom. Without the defence instructing another expert to review the evidence it is entirely possible this could go unnoticed, and realistically it is likely there are undetected miscarriages of justice where cases have relied heavily on digital evidence.”

A report published by the Police Foundation in January recommended that training in digital forensics be provided for everyone working within the criminal justice system, including judges, prosecutors and defence barristers, to help reduce instances of misinterpretation and better understand the limits of what can be achieved.

The Police Foundation’s director, Rick Muir, said: “There may always an element of subjectivity in this, but we could try to reduce the room for error through effective training and the use of common standards across digital forensics work. Most examination is done in-house, so I think there’s a real onus on the police to make sure that consistent standards are applied.

“If it loses credibility, that’s a massive problem because almost any criminal case these days will have some kind of digital evidence. You could have people who were wrongly convicted or people who are guilty going free, and there’s a wider issue of undermining public confidence in digital forensics if you don’t get this right.”

A spokesperson for the National Police Chiefs’ Council said: “Digital forensics is a growing and important area of policing which is becoming increasingly more prominent as the world changes. This report is from a very small sample size and is not representative of the operational environment police in this country work in. We are always looking at how technology can add to our digital forensic capabilities and a national programme is already working on this.”
Newsletter

Related Articles

0:00
0:00
Close
Corporate America Cuts Middle Management as Bosses Take On Triple the Workload
Parents Sue OpenAI After Teen’s Death, Alleging ChatGPT Encouraged Suicide
Amazon Faces Lawsuit Over 'Buy' Label on Digital Streaming Content
Federal Reserve Independence Questioned Amid Trump’s Push to Reshape Central Bank
British Politics Faces Tumultuous Autumn After Summer of Rebellions and Rising Farage Momentum
US Appeals Court Rules Against Most Trump-Era Tariffs
UK Sought Broad Access to Apple Users’ Data, Court Filing Reveals
UK Bank Shares Dive Over Potential Tax on Sector
Germany’s Auto Industry Sheds 51,500 Jobs in First Half of 2025 Amid Deepening Crisis
Bruce Willis Relocated Due to Advanced Dementia
French and Korean Nuclear Majors Clash As EU Launches Foreign Subsidy Probe
EU Stands Firm on Digital Rules as Trump Warns of Retaliation
Getting Ready for the 3rd Time in Its History, Germany Approves Voluntary Military Service for Teenagers
Argentine President Javier Milei Evacuated After Stones Thrown During Campaign Event
Denmark Confronts U.S. Diplomat Over Covert Trump-Linked Influence in Greenland
Starmer Should Back Away from ECHR, Says Jack Straw
Trump Demands RICO Charges Against George Soros and Son for Funding Violent Protests
Taylor Swift Announces Engagement to NFL Star Travis Kelce
France May Need IMF Bailout, Warns Finance Minister
Chinese AI Chipmaker Cambricon Posts Record Profit as Beijing Pushes Pivot from Nvidia
After the Shock of Defeat, Iranians Yearn for Change
Ukraine Finally Allows Young Men Aged Eighteen to Twenty-Two to Leave the Country
The Porn Remains, Privacy Disappears: How Britain Broke the Internet in Ten Days
YouTube Altered Content by Artificial Intelligence – Without Permission
Welcome to The Definition of Insanity: Germany Edition
Just a reminder, this is Michael Jackson's daughter, Paris.
Spotify’s Strange Move: The Feature Nobody Asked For – Returns
Manhunt in Australia: Armed Anti-Government Suspect Kills Police Officers Sent to Arrest Him
China Launches World’s Most Powerful Neutrino Detector
How Beijing-Linked Networks Shape Elections in New York City
Ukrainian Refugee Iryna Zarutska Fled War To US, Stabbed To Death
Elon Musk Sues Apple and OpenAI Over Alleged App Store Monopoly
2 Australian Police Shot Dead In Encounter In Rural Victoria State
Vietnam Evacuates Hundreds of Thousands as Typhoon Kajiki Strikes; China’s Sanya Shuts Down
UK Government Delays Decision on China’s Proposed London Embassy Amid Concerns Over Redacted Plans
A 150-Year Tradition to Be Abolished? Uproar Over the Popular Central Park Attraction
A new faith called Robotheism claims artificial intelligence isn’t just smart but actually God itself
Deputy Prime Minister Angela Rayner Purchases Third Property Amid Housing Tax Reforms Debate
HSBC Switzerland Ends Relationships with Over 1,000 Clients from Saudi Arabia, Lebanon, Qatar, and Egypt
Sharia Law Made Legally Binding in Austria Despite Warnings Over 'Incompatible' Values
Italian Facebook Group Sharing Intimate Images Without Consent Shut Down Amid Police Investigation
Dutch Foreign Minister Resigns Amid Deadlock Over Israel Sanctions
Trump and Allies Send Messages of Support to Ukraine on Independence Day Amid Ongoing Conflict
China Reels as Telegram Chat Group Shares Hidden-Camera Footage of Women and Children
Sam Nicoresti becomes first transgender comedian to win Edinburgh Comedy Award
Builders uncover historic human remains in Lancashire house renovation
Australia Wants to Tax Your Empty Bedrooms
MotoGP Cameraman Narrowly Avoids Pedro Acosta Crash at Hungarian Grand Prix
FBI Investigates John Bolton Over Classified Documents in High-Profile Raids
Report reveals OpenAI pitched national ChatGPT Plus subscription to UK ministers
×