Police Minister Judith Collins says police officers are spending more time on the roads despite a reduction in the number of patrol cars.
She says this shows the effectiveness of National's decision to cut the police car fleet.
Labour says the reduction sends an appalling road safety signal.
But Ms Collins says the policy simply represents a better use of resources as cars are being used more.
She says there was an increase of 5% in the distances covered by police officers last year, from 90 million km in 2008 to 94 million km.
And she says there was a decrease in the road casualty toll in the last three months of last year, when the vehicle cuts began.