CPS Prosecutor Cited a Nonexistent Case in High Court

A prosecutor for the Crown Prosecution Service (CPS) told England's High Court that a legal precedent supported her case, and the precedent did not exist. The Guardian understands it came from an AI answer produced during an internet search.

An explanation the judges rejected

Ravinder Dhillon, a senior crown prosecutor in the CPS rape and serious sexual offences unit, took the decision to proceed in April, and the chief crown prosecutor confirmed it. In October she admitted the citation was a mistake. She said she had meant a different, real decision made 15 years earlier.

Two senior High Court judges called her explanation "unsatisfactory". The court said the invented reference did not change the outcome of the challenge.

The CPS says it has a strict AI policy that keeps the technology out of legal decisions and requires human checks for accuracy. A spokesperson said the error came from legal research done on the internet, and that the search returned an AI summary containing the fictional case details. It was fixed as soon as it was found, the spokesperson said, and an internal review checked whether other cases were affected. The CPS has since shared the lesson that case law must be cited from trusted legal sources.

The case behind the citation

The dispute concerned whether a boy should be prosecuted for the rape of his younger sister. He was 11 at the time of the alleged offence and she was seven. His lawyers challenged the decision to prosecute. They said prosecutors had not considered submissions from a forensic psychologist, social workers and youth workers.

Dhillon argued for prosecution and cited a case she called CPS – R v J [2024] EWCA Crim 3529. No such case exists. The boy's trial is scheduled in the youth courts, later this week.

A second CPS error, and a growing list

In February the CPS admitted that a lawyer in an extradition case involving two Romanians had cited nonexistent authorities, probably because of AI. Opposing lawyers spotted those, because they could find no trace of the cases. The CPS concluded then that the risk of recurrence was low. This is only the second known CPS case.

The latest incident takes a UK tracker kept by barrister Matthew Lee of Doughty Street Chambers to 101 entries. It covers confirmed, suspected and disputed AI errors and related false citations. Lee said the cases found may be the "tip of the iceberg", since many lower court decisions are never published. He also raised privacy and confidentiality risks in the CPS using AI, given how sensitive its material is.

What experts and courts have said

Brian Flanagan, an associate professor of law at Maynooth University who studies the use of AI by judges, described the lapse as a serious failure. He said the time AI saves raises the risk of such errors. He added that the stakes are higher when the lawyer works for the state, given its power.

Courts have been dealing with the problem for some time. In June 2025 the High Court asked the Bar Council and the Law Society to consider steps to curb it urgently. Dame Victoria Sharp, then president of the King's bench division, warned that lawyers misusing AI could face sanctions that range from public admonishment to contempt of court proceedings and referral to the police.

Our View

Most earlier errors came from people without legal training who represented themselves. A state prosecutor making one in a case against a child is a different matter. The open question is verification: the error reached a High Court argument, and the CPS has not said whether its review found anything else. A third case would test its policy of human checks.

Source: The Guardian