It is claimed the disclosure led to an article which appeared on the Daily Mirror website in February this year.
The IPCC independent investigation concluded there is no evidence to suggest that the disclosure was made by any police officer or member of staff working on the Operation Sacristy team.
The investigation examined a formal note of a conversation and emails between the head of Corporate Communications at Warwickshire Police and a Daily Mirror journalist shortly before the article appeared. While no individual as a source for the story is identified, that evidence indicates the source was not from any police force. The Daily Mirror journalist declined to reveal their source to the IPCC investigation.