Originally Posted by celle

However, it is usually the driver who is fined if passengers are not complying with the law.

Originally Posted by NZTA

If you're the driver, the law says it's your responsibility to make sure that everyone under 15 years old is wearing a safety belt or sitting in an approved child restraint.

(However, the driver of a passenger service vehicle – such as a bus or taxi – is not legally responsible for ensuring seatbelts are used, if fitted.)
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Drivers and passengers 15 years and over must wear a safety belt if there's one available.
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If you don't wear a safety belt, or you allow a person under 15 years to travel unrestrained, you can be fined $150 for each belt not worn. The driver must pay for each unrestrained person under 15 years old. People 15 years and over are responsible for their own fine.
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