The family of a Gisborne man killed by gang members is seeking an apology from police and has made a complaint to the Police Complaints Authority.

A High Court jury last night found one man guilty of the murder of Anton Newcomb and three others guilty of manslaughter. A fifth was found not guilty of manslaughter.

The two-week trial followed the death of Mr Newcomb who was stabbed outside the Irish Rover Bar in the early hours of August last year.

But his father Mathew says there are two major unresolved issues - the fact that police did not notify him of his son's death and that it could have been prevented.

The family was seeking a public apology from the officer in charge of the Gisborne Police district Inspector Waata Shepherd.

Mr Newcomb said he was contacted by another son, Harvey, who told him that something had happened to Anton.

He went to the Gisborne police station about 9.30am. An officer came out of an interview room and told him "your son has just been murdered."

"I just broke down. I had to be taken to Victim Support," said Mr Newcomb.

Two months after the murder he and his grandson Isaac went to the police station for a meeting with Inspector Shepherd.

"I asked him why wasn't I notified about my son's death?" "Inspector Shepherd said: 'we only get in touch with the next of kin if we have to."'

The family also believed the murder was preventable.

Evidence was given at the depositions hearing and the murder trial that a witness had been told well before the killing that a group was going to "take Anton out."

The witness said he tried to stop police but was ignored.

In March the family made a complaint to the Police Complaints Authority and was still waiting for a decision.

Mr Newcomb said the verdict had taken a load off their chests but they would not get closure from the death of Anton until the two outstanding issues were resolved.

Inspector Shepherd said he could not comment because the matter was before the complaints authority.