After he admitted a "sustained campaign of intimidation" against Scott and Kylee Guy, Ewen Macdonald knew he was in the frame for murder.

"I can see the finger points at me," he told police on April 7 last year as he denied killing Mr Guy.

"But I'm not that blimmin' psycho."

Earlier in the interview, Macdonald had stuck to his lies about the burning of the old farm house waiting to be removed from the Guys' side of the farm on October 24, 2008. He slept through the night, he said.

Then on January 30, 2009, the inside of the Guys' new house was vandalised and offensive graffiti was tagged to the outside.

Macdonald said he was up north that night.

But he later changed his story.

A DVD of the interview, which lasted about 4 1/2 hours, was played to the jury at Macdonald's murder trial in the High Court at Wellington.

Macdonald is accused of shooting Mr Guy, his brother-in-law, at 4.43am on July 8, 2010, at the gates of Mr Guy's Aorangi Rd property in rural Feilding.

The Crown says he then biked back to his house, 1.47 kilometres away, before turning up for work as normal.

The defence says Macdonald is not the killer.

On April 7, 2011, Detectives Glen Jackson and Laurie Howell repeatedly asked Macdonald if he was a murderer. He had no alibi for the morning in question, they said.

Macdonald stuck to his denials, after earlier coming clean about other offending.

But he had done that only when Mr Howell said police had a statement from former farm worker Callum Boe.

Mr Howell asked Macdonald what he thought it said.

"If he was with you during any of the offending and he's told the truth about it, what do you think he said?"

"That he had nothing to do with it," Macdonald said.

"He didn't say that. What do you think he said?"

"He said he was probably involved."

Macdonald then admitted to stealing two deer from a Colyton property in 2006 and torching the house with Mr Boe.

When asked what he was trying to achieve, Macdonald said he "just thought it would be funny".

"It wasn't directed at Scott and Kylee in vengeance or revenge. It certainly wasn't that."

It was a different matter with the criminal damage and graffiti in 2009.

Macdonald said he wasn't over Mr Guy saying at a 2008 meeting that he should take over the farm and Macdonald could only stay as a worker.

"I still was holding a bit of a grudge. It wasn't a fair partnership, just with the hours I had to work and I didn't get to spend as much time at home with the kids, whereas Scott got a lot more home time. To me it just felt like I was working my arse off and it wasn't equal, the hours we worked."

Macdonald said he and Mr Boe set off for Ruakaka, to move a friend's belongings, after the damage.

On that occasion and for the arson, the pair had used push bikes to travel along Aorangi Rd to avoid being seen or heard.

Defence lawyer Greg King later revealed to the court that Macdonald was awaiting sentence for those offences.

In the interview, Detective Laurie Howell asked Macdonald if his "sustained campaign of intimidation" culminated in murder.

"I had nothing to do with it," Macdonald said.

"I would sooner have Scott there working. Now it's a total pain in the arse. I've had to work harder than what I have before."

Mr Jackson asked Macdonald about an earlier comment he made, when he agreed with a suggestion from his father Kerry that whoever did the arson and criminal damage was the murderer.

"I'm not the murderer," Macdonald said.

"I would say you're going to charge me with murder, but I'm not guilty."

Macdonald also denied leaving three notes in the Guys' letterbox in late 2008 and early 2009.

After the criminal damage, one note said: "Now you know how it feels to lose something you love."

"Honestly, I don't know anything about that," Macdonald said.

"What concerns me is those letters ... Is there someone else out there?"

After the interview Macdonald was arrested and charged with murder.

"I guess I won't be going home tonight," Macdonald said.

"I doubt it very much," Detective Laurie Howell replied.

Macdonald made his first appearance in the Palmerston North District Court on April 8, 2011, after being remanded in custody. Police test bike theory P2

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