A large portion of family violence went unreported for a number of reasons.
Victims would also routinely ring police a few days after reporting an assault wanting charges dropped.
"That's why the family violence dynamics are so difficult to deal with," he said.
Police did their best to support victims and could put them in contact with Women's Refuge, Victim Support and local family violence intervention groups.
Mr Moore advised those in relationships they were concerned about to contact a support service.
"What they can't do is just sit on their hands and hope the problem goes away. They've got to reach out and seek support."
Abuse of older people in the community by family was an emerging trend, which groups like Age Concern could help with. Parentline could help where parents were having trouble with teenage children. There were also Pacific, Maori and Asian support providers available.
Mr Moore said people didn't need to wait until they had to call emergency services to seek help.
"People can take steps before that point."
Nationwide, 69 per cent of offenders in the 2313 acts intended to cause injury this June were known to their victims and in 44 per cent of cases the offenders and victims were family.
Victims were known to their offenders in 38 per cent of New Zealand's 21 homicide and related offences this June. In two cases, the victim and offender were family.
In 9 per cent of New Zealand's 558 burglary cases this June, the victims knew the offenders. In six cases, they were family.
Women's Refuge chief executive Ang Jury said police believed they only saw about 20 per cent of family violence cases.
"To encourage more reporting we need to have victims convinced that they're going to be treated seriously when they do report and that something's going to happen."
Those concerned about relationships with family and friends should talk with police or an agency such as Women's Refuge.
"Family violence, in particular, thrives best in silence and in secrecy," said Dr Jury.
Victim Support service delivery general manager Angela Crawford said it was a "very sad fact" that so many offenders were known to their victims.
Ms Crawford said Victim Support tried to market itself so people knew they were just a free and confidential phone call away and always available to talk about crime or abuse or to respond to queries.
Victim Support worked with people in crisis situations, assessing danger and needs and advising victims of the best steps to take.
It could also listen refer victims to counselling services and help with police and court processes.