The father of murdered Manawatu farmer Scott Guy has admitted he initially lied to police about a shotgun kept on the family farm.

Bryan Guy took the witness stand at the murder trial of Ewen Macdonald - his son-in-law - in the High Court at Wellington on Wednesday.

Macdonald is accused of shooting dead Scott Guy in the driveway of his Aorangi Road property on the outskirts of Feilding on July 8, 2010.

A shotgun belonging to Bryan Guy has been produced as evidence in the case.

After his son's death, Mr Guy told police that he always kept the shotgun broken down in a safe that required a key and a combination.

However, for a time leading up to Scott's death, the shotgun had been used to scare birds away from silage on the family farm, and instead of locking it away Bryan Guy had actually kept it hidden in and behind a cupboard in the farm office at 147 Aorangi Road, where Macdonald lived.

Mr Guy admitted to police in April 2011 that he had not told the truth about where the gun was kept.

Asked in court whether he admitted lying to police, Mr Guy said: "Yes, and I regret it."

Under cross-examination from defence lawyer Greg King, Mr Guy said he was absolutely sure Macdonald did not know the shotgun was stored in the office.

Mr Guy said that on the day of his son's death, the shotgun was as he had left it, and he returned it to the safe.

He also advised Macdonald to ensure his own gun was also locked away.

Mr Guy said he would "absolutely" have told police if he had any cause for concern about his shotgun, and said he initially lied because he had always been conscious about gun safety.

"This time, I'd broken my own rules," he told the court.

Earlier, Mr Guy recalled the phone call from Macdonald that first informed him of his son's death.

"Ewen was very distressed when he rang me. He was almost incoherent," Mr Guy told the court.

"He said something along the lines of 'something's happened to Scott', I remember him saying [something about] 'his face' ... 'you'd better come out here'."

The neighbours who first discovered Scott Guy's body told the court it appeared his throat had been cut.

However, Mr Guy said he recalled someone at the scene telling him his son had been shot, although he could not remember who said that.

The trial is continuing before a jury of 11.