But after 16 months, Operation Midland was closed down, prompting Sir Bernard Hogan-Howe, the Metropolitan Police Commissioner, to order an internal review.

The report by Sir Richard Henriques, a retired High Court judge, is expected to be passed to the police next month and is likely to be highly critical of senior officers, who said Nick’s testimony was “credible and true”.

A summary of the allegations Nick made against Lord Janner, whom he claimed was part of the VIP ring, have been made public by the deceased peer’s family. They described the supposed evidence as “preposterous”.