Evidence given to judge reads like extract from a spy thriller
But it does highlight the level of suspicion among staff working in the Garda Siochana Ombudsman Commission (GSOC).
This distrust increased when UK counter-surveillance company Verrimus was hired to carry out a security sweep of GSOC's office.
Among the reasons GSOC called in the security firm was the belief their mobile phones were being interfered with.
Officials claimed phones charged overnight would run out of battery within two hours, which they believed was because of interference.
A GSOC officer bought a 'pay-as-you-go' mobile phone and called Verrimus to enlist the company's services.
During Verrimus's first inspection it detected two possible threats – the wireless device connecting to an outside 3G network and the anomalies on the chairman's telephone line.
During the firm's second visit it was established the wireless device was connecting to a network coming from a local Insomnia coffee shop.
A Verrimus expert, who is not named, claimed two individuals were "making inordinate attempts to watch what they were doing from the street" during the inspection.
A colleague, who was monitoring the Insomnia coffee shop, then noticed a customer carrying a "nylon sports bag" containing a "large box-shaped item".
The Verrimus employee, who was a former police detective, believed this was an indication of "localised technical intelligence gathering".
A GSOC official also gave evidence claiming he noticed a white van with blacked-out windows parked on the street opposite the Garda Ombudsman's headquarters.
He later went to investigate the person who allegedly had a handheld device in the local cafe.
When he was on the street he noticed two men walking together on three occasions. When they saw him the third time, they turned and walked away.
The expert's evidence also includes details of telephone calls he received from a businessman after the inquiry was announced.
The businessman sold surveillance equipment in Ireland and was interested in establishing a business relationship with Verrimus.
The conversations are described in the Cooke Report as "lengthy and quite oblique".
"One theme appears to have been a desire on the part of the individual to convey concerns that had been expressed to him by contacts in both the Garda Siochana and Irish Army Security Services," Mr Cooke added.
GSOC expressed concerns about these conversations and claimed this was an attempt to influence the inquiry.
Mr Cooke concluded that the psychical surveillance and the telephone calls suggested it was Verriumus who were been monitored rather than GSOC.