Senior judge: Put AI in charge of reviewing social media evidence

A senior judge has said that "technology has created many of our current disclosure problems" – and then added that AI will fix them.

Lord Justice Gross, a Court of Appeal judge, gave a speech last night to the Criminal Bar Association in which he reviewed the ongoing criminal cases disclosure scandal.

Originally arising from questions over why rape trials were collapsing at the last minute, the disclosure scandal hinges on how police employees and Crown prosecutors were processing evidence, especially social media evidence, which in certain cases proved that people accused of some of the most serious crimes were in fact innocent all along.

The law says that prosecutors must hand over evidence that undermines their own case to the defence. Predictably, given the mark-your-own-homework situation these rules created, this failed to happen consistently or quickly enough.

For his part, Lord Justice Gross said that in one case investigated by London's Metropolitan Police, "it took 630 hours for the police disclosure team to review the content of the three complainants' mobile phones and their Facebook accounts".

"In another and more straightforward rape case, where complainant and defendant met on Tinder and there were only two mobile phones to consider, 150 officer hours were required to examine 20,000 items of data," said the judge.

As a solution he proposed that artificial intelligence ("computers learning from feedback to make accurate decisions") be used to help prosecutors trawl through digital evidence instead of humans doing so, adding: "Pending the further advance of technology, a resolute focus on the application of existing law, using the tools available and in accordance with now well-established duties, provides the best way of minimising disclosure failures."

Police investigators obtain evidence, including by downloading the contents of mobile phones and examining social media accounts, and then review it together with CPS prosecutors before a trial to decide what to hand over and what to keep to themselves. Barristers who prosecute criminal cases at court have limited involvement, though the scandal was truly kicked off when barrister Jerry Hayes, instructed by the CPS to prosecute a student accused of rape, turned in withheld evidence his own side had gathered.

In January this year the CPS said it had dropped 900 criminal cases after reviewing the practice of withholding evidence, while earlier this month it also said that 47 rape cases had been dropped altogether for the same reason – including a dozen cases where innocent people had been sent to prison while awaiting trial.

Lord Justice Gross concluded that "the law is satisfactory" on disclosure. His full speech can be read on the judiciary website in a nine-page PDF. ®

Sponsored: Continuous Lifecycle London 2018 - Early Bird Tickets Now Available