The Government is considering introducing 'R' plates for drivers on restricted licences in an effort to reduce the road toll.
A Ministry of Transport report shows that 620 people were killed in crashes between 2006 and 2010 where high-risk drivers were at fault.
It says most high-risk drivers are defined as males under 30 years.
Motorists as young as 16-and-a-half can hold an restricted licence, in which driving must be supervised between 10pm and 5am.
Dorothy Begg of the Otago University Injury Prevention Research Unit says young people are most vulnerable when they gain their restricted licence.
Dr Begg told Radio New Zealand's Nine to Noon programme that displaying an 'R' plate helps enforcement, as it makes clear which drivers have restricted licences.
The Automobile Association says introducing 'R' plates makes good sense, as it could stop drivers carrying passengers illegally.
Spokesperson Mike Noon says young drivers without full licences carrying passengers are a major concern.
"We have a lot of problem with young drivers who aren't yet fully qualified, don't yet have their full licence, driving with passengers, having crashes and it's not only them, it's also the passengers which are hurt."
The association says having to display an 'R' plate may work as a deterrent.