Senior Nats leaking emails is fiction: Key

Prime Minister John Key says the notion that senior members of his party leaked documents to journalist Nicky Hager is "bollocks" and "fiction put out by the left".

Police yesterday released a police investigation into how 475 emails from former National leader Don Brash came into Mr Hager's hands. It found that it was "highly unlikely" that the system was hacked, and leaned towards an inside job.

The emails formed the basis of The Hollow Men, and Dr Brash resigned soon after it was released.

When asked if there had been a leak from senior National Party sources, Mr Key said: "That's a great, sort of, nonsense, fiction put out by the left.

"Or bollocks is another way of putting it."

He firmly believed that the system had been hacked into - "but I can't back that up" - and he had a theory on who it was.

When pressed by journalists, Mr Key said: "There's no question other people had access to that system. It's a statement of fact. There are contractors that had access to those old systems.

"The system had no capability of knowing who went in and out of it. That was one of the faults of the system."

Mr Key said he was not worried about his email being hacked.

"I'm not in the process of sending dodgy emails, but at the end of the day someone can always cut and paste and break into the system."

Mr Hager said Mr Key's reaction was "shocking".

"For the Prime Minister at the end of all that [investigation] to repeat the same baseless allegations is shocking.

"The main way information comes and goes from offices and organisations is the people who come in and out the doors. It doesn't suit them to admit that so they will keep repeating something even in the face of strong evidence to the contrary from the police inquiry.

"Any reasonable person reading this result will give up those diversions about hacking and stealing."

He maintained there had been a mixture of sources close to and inside the National Party.

"They weren't people dressing up as cleaners, or whoever they might be fantasising."

Mr Key said the email saga would probably remain an "unsolved mystery".

POLICE BRASH EMAIL REVIEW

* Review into police investigation of Don Brash's emails, launched after Dr Brash said it was politically biased, "cavalier" and he had not been kept properly informed of progress.

* An "unreasonable and unacceptable" delay in getting the final report to Dr Brash, who received his copy over a year after being told it was forthcoming.

* Recommends new way of handling complaints of a political nature, and that Wellington police look at how they record files and OIA requests, and reassign files when officers resign.

* Found investigation was competent.