University of Otago dean of law Prof Mark Henaghan made the comments in response to growing calls for changes to legal protection orders following the St Leonards shootings this week.
Labour Party justice spokesman Andrew Little and women's affairs spokeswoman Carol Beaumont released a joint statement yesterday calling for a review of legal protection orders following the deaths of Bradley and Ellen Livingstone at St Leonards earlier this week.
The statement suggested changes to the Domestic Violence Act, such as giving police the power to issue protection orders, where they deemed a situation to be dangerous, rather than relying on a potential victim to apply for an order.
They also suggested moving the issuing of protection orders from the Family Court to the jurisdiction of the district court, which would ''move the focus from one of conciliation to one of enforcement''.
However, Prof Henaghan said such proposals were ''silly'' and a ''bit of a slap in the face to family court judges''.
''Family court judges do grant protection orders and they do know these matters well. They take it very, very seriously,'' he said.
He did agree a review should take place and would be ''helpful to look at where the gaps are''.
''It's a review to see that everyone is playing their part,'' he said.
''It has to look at the reality of what's happening on the ground.''
It needed to assess whether groups like Women's Refuge had adequate resources to provide support and care, he said.
He also believed cultural change needed to take place throughout New Zealand, as domestic violence was ''pretty endemic in our country''.
''We need to have a whole community that says [to abusers] what you are doing is wrong and we will help you to change.''
Statistics supplied by the Ministry of Justice showed there had been 13,000 final protection orders granted in New Zealand between July 2008 and June 2013, and more than 9000 people have been convicted of breaching protection orders in the same period.
A Ministry of Justice spokesman said the statistics did not show that two-thirds of orders had been breached, as once orders were issued, they remained indefinitely and there could be tens of thousands of orders active, although the ministry was unable to provide those numbers.
Prof Henaghan said the high number of breaches was symptomatic of a culture when domestic violence was common, not of an ineffective law.
''Legislation is only the tip of the iceberg. The Act is pretty good; it's got the widest definition of domestic violence in the world probably. The real issue is whether it's being applied consistently across the country.
''It's not the law, it's how we apply it and what's in our hearts and minds and how seriously we take it.''
Justice Minister Judith Collins - whose cousin was killed by her estranged husband after he breached a protection order - told the New Zealand Herald the system had been reviewed in the Family Court reform process.
That resulted in the Government increasing penalties for breaching protection orders from two years' imprisonment to three.
''The issue in this case is that this person wasn't imprisoned, otherwise this wouldn't have happened,'' Ms Collins said.
She said that with the increased penalties, Parliament was trying to send a message to judges that ''we expect people to face the full penalties available should they continuously breach these orders''.
But such cases were difficult for judges to deal with.
''I'm not someone who blames the judges or those who try to stop this happening. The full blame must be with the offenders.''
She said that before Christmas she had asked officials to work on measures to further toughen up enforcement of protection orders.
''They're doing some work for me, including giving the judiciary the power to impose GPS monitoring,'' she said.
The GPS devices attached to an offender send out a signal every minute. If the offender strays into ''exclusion zones'' near victims an alarm sounds at the Corrections Department offices in Wellington.
Officials call police in the region immediately, or on some occasions ring the offender directly to warn them to leave the area.
Ms Collins expects to be updated next week.
Tim Black, of the Law Society's family law section, said it appeared the protection order system was working because Ms Webb was able to obtain an order and breaches of that order were dealt with by police and the courts.
But ''a piece of paper by itself can't stop someone acting in this way''.
Women's Refuge chief executive Heather Henare said all breaches of protection orders ''should be treated with the full force of our law'', and offenders who threatened to kill ''should be treated in the most high-risk category with strong consequences''.
