From December 1 last year, the alcohol limit for drivers aged 20 and over was lowered from 400mcg of alcohol per litre of breath to 250mcg.
"The early indications are that people are adjusting to that change in the drink drive limit," he said.
"We're getting fewer people at the court-level offence than what we've previous had."
Mr McKennie said he had spoken to people who had travelled from Wellington to Auckland on the weekend.
"They've found overall driver behaviour was very good, with very few incidents of people driving recklessly and unsafe behaviour, which is very promising."
Mr McKennie said he wanted the messages from the holiday weekend to carry through to everyday driving.
"It's not just about holiday weekends. We want people to get this embedded in their everyday driver behaviours," he said.
"It's getting people to pay a high level of attention to their driving at all times."
One person died at the scene of a two-car collision in Canterbury on Saturday afternoon.
The crash happened on State Highway 8 between the Lake Pukaki Visitor Centre and Mt Cook Rd. A second person was flown to Christchurch Hospital in a serious condition.
A second death on the roads is unlikely to be included in the official road toll, after a truck driver died at the wheel in Auckland on Saturday.
The man was aged in his 50s, and was believed to have died as a result of a medical event around 10am on Waipa St, Birkenhead.
Last year's Easter road toll was five, from a reported 95 injury crashes.
Three people were killed on the roads in 2013 over the Easter holiday period. The only fatality-free Easter ever recorded was in 2012.
