The UK government will examine the role of computer evidence in the criminal justice system through a call for evidence to prevent future miscarriages of justice, following years of proceedings relating to the Horizon Post Office scandal.

The government’s call for evidence highlights the misnomer that computers, and the evidence they process, are infallible until proven otherwise.

The limitations of this notion, however, were highlighted by the wrongful convictions of hundreds of innocent sub-postmasters in the Post Office Horizon scandal.

Faults in the Post Office’s accounting software – which was denied by the Post Office for years – proved the fallibility of digital evidence and the potential for devastating miscarriages of justice if evidence is not thoroughly interrogated, and if testimonies of people dealing with the technology are not believed.

By seeking new ways to ensure people are better protected from miscarriages of justice, the review aims to help build on the government’s broader efforts to restore public confidence in policing and the criminal justice system through its Plan for Change announced this week.

Computer evidence forms a substantial part of many modern prosecutions, particularly in crimes such as fraud, which can involve thousands of digital documents. Digital evidence is also often used in rape and serious sexual offence cases.

Any change requiring the prosecution to prove any computer deice works correctly could impact how quickly cases can be completed, meaning that any legislation affecting this must be well though out and future proofed.

The call for evidence is therefore seeking expert input on how computer evidence should be defined and what could fall into scope of any change to the law.

Distinctions may be made between text messages and social media posts and evidence which has been specifically generated by a computer system or software.

It will further seek views from organisations and individuals with experience of the criminal justice system, along with those with expertise in computers and software.

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The government did clarify that the miscarriages of justice which occurred in the Post Office cases were down to deliberate failures to properly interrogate and disclose evidence – which prevented postmasters and others from effectively challenging the reliability of the Horizon computer system evidence.

Any changes to the presumption would not be able to further protect against instances where parties mislead a court on the accuracy of the evidence – this would count as perjury, a separate crime.

However, removing or changing this presumption could mean defendants are better equipped to interrogate computer evidence against them, and would put more onus on the party supplying the digital evidence to ensure it can stand up to scrutiny.

“We must learn the lessons of the Post Office scandal,” justice minister Sarah Sackman KC said.

“A blanket ‘no questions asked’ acceptance of the accuracy of digital evidence can have a devastating impact on people’s lives.

“We need to carefully consider how we can both use and interrogate digital evidence in court. Ensuring people are protected from miscarriages of justice is vital, and one part of the government’s Plan for Change.”