Top judges have criticised serious failures by police and prosecutors to disclose evidence of police corruption in an international fraud case.

Judges in the Court of Appeal outlined their “grave view” of the failure by the Metropolitan Police and Crown Prosecution Service (CPS) to hand over intelligence that could have undermined the case against James Ibori, a former Nigerian politician. Ibori, 58, once governor of Delta State, pleaded guilty in 2012 to laundering almost £50 million.

However, it has since emerged that the Met had had intelligence since 2007 that one of its investigating officers was being paid for information about the case. The authorities denied its existence for years.

Ibori is appealing against his conviction on the ground that, had he been told about the corruption intelligence, he would not have pleaded guilty.

In February senior judges raised serious concerns about the disclosure failures while rejecting an appeal by Ibori’s solicitor, Bhadresh Gohil, who was convicted for being an accomplice in the money-laundering plot.

Lord Justice Gross, sitting with Mr Justice William Davis and Mr Justice Garnham, criticised the “erroneous approach” to disclosure and said that the failures were “eminently avoidable”. Their judgment read: “We do not minimise the prosecution’s disclosure failures in this case. To the contrary we take a grave view of them. As recent events have yet again emphasised, disclosure failures can cause great injustice.”

The judges did not overturn Gohil’s conviction in part because he had knowledge of the alleged police corruption at the time of the trial but did not use it.

Judges outlined at least four occasions in 2013 and 2014 when there were opportunities for the authorities to have disclosed the evidence, which did not come to light until 2016, and pointed to a “serious communications breakdown within the prosecution team”.

The CPS conducted a review of the disclosure failures in 2016 which was criticised by Sasha Wass, QC, lead counsel in the Ibori and Gohil prosecutions, who said its findings obfuscated the issues.

In November 2016 she wrote to Alison Saunders, the director of public prosecutions (DPP), that the failure to carry out a proper disclosure review “allows the police role in bribery and its concealment in five separate trials over eight years to go unreported”. She was referring to the Ibori case and linked accomplice trials. Ms Wass has also claimed in correspondence to the DPP that she and the CPS were “seriously misled” for years by Met detectives over the source of the corruption intelligence. She said its relevance was hidden from counsel.

Her account received backing from Lord Justice Gross, whose judgment concluded that it was “fanciful” that Ms Wass and her junior would have deliberately misled the court.

Met detectives told a hearing during Ibori’s appeal in March that Ms Wass and her junior barrister were aware of the evidence much earlier. A row has since broken out after Ms Wass complained that Jonathan Kinnear, QC, who replaced her as lead counsel, had revised his position to “champion the position of the police”.

Ms Wass said last night that there were “numerous missed opportunities” to disclose the police intelligence to the three QCs involved in the case and that she immediately took appropriate steps when told of its relevance. She said she could not comment on the Ibori appeal.

A CPS spokesman said its review found material that should have been disclosed but it was inappropriate to comment further while proceedings continued.

The Met said that the corruption allegations were thoroughly investigated and did not result in arrests, charges or identifiable misconduct. Mr Kinnear said it would be inappropriate to comment while the case was considered by the Court of Appeal.

Judges have asked the prosecution to respond before they rule on the Ibori appeal.

•Text (excluding headline) courtesy of Times of London.

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