A massive drop in murders and overall drop in New Zealand crime during 2010 could be quickly reversed if police are targeted by Government cuts to the public sector, the Police Association says.

Recorded crime dropped 5.6 per cent in 2010, or 6.7 per cent when adjusted for the increases in New Zealand's population, in what Police Minister Judith Collins has called a tribute to intensified crime fighting.

There were 426,345 recorded offences last year - a 25,000 reduction from 451,405 in 2009.

That included a 29 per cent drop in murders from 65 in 2009 to 46 last year, police said.

The last time the murder rate was that low was in 2004, when 45 were recorded, according to Statistics New Zealand figures.

Police association president Greg O'Connor said the gains were down to extra investment which has seen 1000 extra police officers added since 2006.

"For the first time in many years, police are now able to act proactively across a range of areas including organised crime and methamphetamine, instead of being constantly short-staffed and able to do little more than rush from one emergency call to the next."

However, those gains were "extremely fragile" and could be reversed if a razor was taken to the police budget, he said.

He called for police to be immune to the public sector job cuts signalled by Finance Minister Bill English and State Services Minister Tony Ryall this week.

"We have to be very careful that we don't undo the good work by turning Police's attention inwards in search of budget cuts, as happened to enormously destructive effect during the late 1990s."

Ms Collins attributed the dropping statistics to "no-nonsense" crime legislation, the introduction of tasers and the dedication of police.

"However, this result does not signal a victory over the criminals. While the decrease is consistent with a long-term trend, our crime rates are still unacceptably high.

"Police are applying intense pressure to criminals, and there will be no let up.

"Armed with hundreds of extra frontline officers, no-nonsense new legislation and new tools such as tasers and digital communications, Police will continue to send a strong message that crime will not be tolerated."

Auckland's police districts recorded the largest reductions in crime in New Zealand.

Waitemata led the country with a 10.9 per cent drop, followed by Auckland City with 9.9 per cent and Counties-Manukau with 7.8 per cent.

All but the eastern police district recorded decreases in total offences.
However, sexual assaults rose from 2912 in 2009 to 3016 in 2010.

Acts intended to cause injury went down from 45,375 to 44,515, but remain markedly higher than the 30,177 recorded in 2000.

Fraud offences had the largest drop of 26.9 per cent, while weapons offences were down 8.9 per cent, drug offences were down 7.7 per cent and burglaries down 3.4 per cent.

Theft and related offences, which made up more than 30 per cent of all recorded offences, dropped by 5.4 per cent.

However, family violence continued to rise nationwide, going up by 655 offences, or 1.2 per cent overall.

The crime resolution rate dropped from 47.8 per cent in 2009 to 47.5 per cent in 2010 due to a reduction in the volume of offences that have high resolution rates, Ms Collins said.

Police Acting General Manager Development, Kevin Kelly said crime in New Zealand had been dropping since 1997.

"Strategies and policies taken at both a national and local policing level, along with partnerships with other agencies, are continuing to make a positive difference in our communities."

Work still needed to be done to stamp out family violence, though it was encouraging to see rates dropping from mid-2010, he said.

"Family violence is unacceptable in any form and communities are showing their intolerance to it. This shows the message is getting through."

Recorded murder figures for the last decade, according to Statistics New Zealand:
2000: 52

2001: 51

2002: 60

2003: 44

2004: 45

2005: 61

2006: 49

2007: 48

2008: 52

2009: 65

2010: 46