The Northern Ireland police officer who headed up a major Jersey child abuse probe is being investigated under the Official Secrets Act for allegedly leaking a memo criticising Jersey’s Attorney General.

Lenny Harper’s successor, Jersey’s Deputy Chief Officer David Warcup, has asked UK police officers to investigate if Mr Harper leaked a private memo to Jersey’s Attorney General detailing his concerns about the collapse of prosecution proceedings against certain suspects.

The memo outlined Mr Harper’s belief that the Attorney General’s office was attempting to obstruct the police inquiry into historical child abuse on the island and was submitted as evidence in a High Court case.

Officers are attempting to establish if the Londonderry man was responsible for the alleged leak and are understood to be pursuing the matter under the Official Secrets Act.

It is believed that a number of journalists have been asked by Sussex police to reveal if the memo had been leaked to them by Mr Harper.

“The document in question was actually lodged with the High Court in London some months back. The document was produced as evidence in the proceedings in the High Court and was subsequently reported in the media. My presumption is that the media obtained it from there,” Mr Harper told the Belfast Telegraph.

A spokeswoman for Jersey States Police confirmed that Mr Warcup ordered an investigation into the alleged leak, but said no further details could be given at present.

Mr Harper is due to give evidence in the High Court in London next month about obstructions he claims he faced while trying to bring cases to court during his time at the helm of the child abuse investigation.

The legal action was launched in August by a campaign group that says it does not have confidence in the island’s authorities.

The island’s attorney general has said criticism of its justice system was “misplaced”.

“The courts of Jersey have been delivering justice week in, week out for centuries. Justice will be done,” he has said.