Following the Post Office Horizon scandal, the Chartered Institute of Legal Executives (CILEX) has welcomed a review of the longstanding legal presumption that computer-generated evidence is inherently reliable in criminal cases.

In its response to the Ministry of Justice’s call for evidence, the organisation stressed the importance of examining digital and software-based evidence critically—especially with the growing influence of artificial intelligence. However, it also warned that reforms should not overcorrect, potentially undermining credible technological tools used in the justice system.

Ultimately, any changes must aim to uphold the principles of fair trials and prevent unsafe convictions.

CILEX stresses, however, that “forcing all computer-generated evidence to be proven to be working correctly for each trial, could be an unnecessary burden on parties, and especially on prosecutors. This would result in substantial costs for whichever party is seeking to introduce the evidence and additional costs for parties who are required to instruct expert witnesses”.

This, CILEX cautions, is a key consideration given the current criminal court backlog stands at over 74,000 cases.

Both experts and statements of truth will be key to ensuring judges have “the necessary confidence” in the evidence and that it is “suitably probative”. CILEX stresses the need for “suitable renumeration and support” to minimise the burden on practitioners and on parties.

Despite these concerns, CILEX acknowledges the difficulties would lessen over time as “it would quickly become established practice that certain thresholds and evidence are required to demonstrate the integrity and condition of the computer-generated evidence”. Once established, practitioners would adjust.

CILEX supports defining computer-generated evidence within the Criminal Procedure Rules and advocates for the re-introduction of a considered and amended s69 of the Police and Criminal Evidence Act 1984, with some caveats, namely that evidence should not be treated as computer generated if it is merely typed on a computer, duplicated electronically or is held or stored on a computer.

CILEX President Yanthé Richardson says: “The devastating miscarriages of justice that resulted from the use of flawed computer-generated evidence in the Post Office Horizon prosecutions, along with the significant developments in technology we have seen over the last 20 years, mean a review of this area of the law is much needed.

“It is vital we make the changes necessary to ensure our laws are fit for the modern age and that digital evidence can be trusted and relied upon in court. We must, however, take into account the additional cost and resources that would be required by those submitting digital evidence, ensuring the definition of such evidence is not drawn too widely and that necessary training and support is available to practitioners ahead of any change.”