Mother caught speeding at over 100km/h with child on her lap - and she had the baby seat in the boot

The boss of a national child safety organisation is "shocked and appalled" at a mother caught speeding at 114km/h with one child across her lap and another unrestrained in the front seat.

The woman, recently pulled over on the Waikato Expressway, has drawn nationwide condemnation after the Waikato Road Policing Team posted the case on its Facebook page, calling it "absolutely heart-wrenching" and "extremely disappointing".

The officer who pulled the woman over walked up to her vehicle to find one young child lying across her lap and another lying unrestrained in the front seat with the seat folded back, with a child booster seat in the car's boot.

She was fined $80 for exceeding the speed limit, $150 for failing to ensure a child under 7 was in an approved child restraint, and another $150 for the child in the front seat also being unrestrained.

Police had also referred the case on "to the appropriate agencies", remarking that "this irresponsible neglectful behaviour and risk to our young ones will not be tolerated". That disgust was shared by Safe Kids Aotearoa director Ann Weaver.

"I'm shocked and appalled," she said.

"I find it so difficult to think why some parents continue to have their children unrestrained."

Although the majority of parents adhered to rules and regulations surrounding child restraints, there remained the few who kept breaking the law.

"And there's absolutely no reason for that. I get really cross, because sometimes it comes down to that attitude we have for our children in New Zealand.

"In some other countries, children are regarded as a priority and so precious, yet we continue to put our children at risk. I can't tolerate that kind of behaviour from parents."

Waikato road policing manager inspector Freda Grace was also dismayed.

"It's not as horrendous as attending a crash scene, but in terms of potential, this is exceptionally disappointing," she said.

"It's disappointing because of the vulnerability of the children - they can't make those decisions for themselves, so they rely on reasonable and sensible adults to do what's best for them.

"And having children riding inappropriately in a motor vehicle is certainly not the best decision for the child, because the whole reason we have rules and regulations around restraints is to ensure children's safety."

The Facebook post has attracted hundreds of likes, more than 100 shares and dozens of responses from outraged commenters.

"Pretty sad really. All the info is out there and obviously these people choose to ignore it," one person said.Others condemned the case as "absolutely disgusting" and "incredibly irresponsible".

According to statistics cited by Safe Kids Aotearoa, 15 children die in car crashes every year in New Zealand.

Children were considered safer in a child restraint until they were 148cm tall.

According to 2008 Starship Children's Hospital data, at least one child a week suffered injuries as a passenger in a vehicle involved in a crash.

Child safety seats, correctly installed and used, could reduce the risk of death by 70 per cent in infants, and by up to 54 per cent in toddlers, and could also reduce hospitalisation by 69 per cent for children under 4.

The organisation encouraged parents to always use the correct child restraint and booster seat for their child's height, weight and age and follow the manufacturers' instructions for sizing and installation of restraints.

Safekids further advised the back seat was safest for children, and to never place a rear-facing restraint in the front seat of a vehicle with an airbag.