The hardest part of Sergeant Pat Duffy's job is telling families that their loved ones won't be coming home ever again.

Sergeant Pat Duffy knows only too well what it's like telling a family their loved ones have been killed in a car crash during the holiday period.

"It was Christmas Day in Auckland and I had to tell them that the people that they were expecting were not coming home – ever."

Duffy, of the Central District highway patrol in New Plymouth, says these conversations "really rock you" and are especially traumatic during the festive season.

"Suddenly those families, instead of enjoying the holiday break with their family, are suddenly having to deal with the loss of a loved one.

"The good times are suddenly gone and then unfortunately for those families the holiday period is a time of mourning instead of celebrating - every year."

SIMON O'CONNOR/STUFF Information released under the Official Information Act shows there is a 68 per cent rise in the number of tickets issued by police in December when compared to the monthly average for the rest of the year. Police say they will be out in force during the holiday period in the hopes of saving lives.

This year's official holiday period began at 4pm on Tuesday December 24 and will end at 6am on Friday January 3, 2020.

As of noon Boxing Day, the New Zealand road death toll, which includes pedestrians, stands at 347. And going on statistics from the past five years 12 people will die on the country's roads during the 10-day holiday stretch.

It's an average of 1.2 deaths a day, slightly higher than the average for the rest of the year, which is 0.9 deaths per day.

It would be trivial to blame the rise on the greater number of motorists on the road this time of year, the more congested traffic and the frustration that brings.

However, these roading conditions and the associated risks are behind the annual, and very public, warnings issued by organisations such as police, Automobile Association and the New Zealand Transport Agency at this time of year.

SIMON O'CONNOR/STUFF Sergeant Pat Duffy says police will be out in force during the Christmas holidays making sure drivers obey the rules.

​NZ Transport Agency acting regional relationships director Ross I'Anson says motorists should prepare for the roads to be busier than normal.

"Congestion and delays are inevitable in peak times, but if everyone leaves plenty of time for their journeys, drives to the conditions and plans ahead before leaving home, there will be less frustration and everyone can concentrate on arriving safely at their destination."

Getting people home to their loved ones is exactly why police will be out in force and taking a hard line on infringements, especially speeding, Duffy says.

The hard line is evidenced in information released by police under the Official Information Act showing the average number of speeding tickets issued nationally jumps significantly in December.

On average there were 99,119 tickets issued during the year in 2019, while in December last year there were 166,497 – which would be a jump of 68 per cent if the same number were issued this December.

In January 2019, 126,976 tickets were issued, a 28 per cent increase on the monthly average for the rest of the year.

ANDY JACKSON/STUFF On average there are 1.2 road deaths per day during the holiday period, slightly higher than the average of 0.9 for the rest of the year. Organisations like police, the NZTA and AA are warning drivers to take their time, plan ahead and be patient this holiday season.

Ministry of Transport statistics show speeding is a factor in 19 per cent of crashes during the holiday period, the second largest contributor behind losing control at 29 per cent.

Alcohol or drugs was a factor in 18 per cent of crashes, inattention 16 per cent, failing to stop or give way 14 per cent and fatigue 9 per cent.

Duffy says issuing tickets is not about revenue gathering but helping motorists realise the deadly consequences of their actions.

"It seems to be the only way that we can try and get the message through to try and get people to slow down.

"The human body isn't designed to withstand the forces involved in a high-speed crash. It's as simple as that.

"We want people to get to their destinations safely so they can enjoy the holiday season with their friends and family."