Police should have more opportunity to let drivers who commit minor traffic offences off with a warning, says Commissioner Howard Broad.

He said the ability to exercise discretion was one of his officers' most valuable tools and if every minor breach of the speed limit was to earn a ticket, speed cameras could do the job instead of people.

Broad said polling showed "enormous support" for police continuing to carry out traffic enforcement.

He said 350-400 people die on our roads a year "and driver behaviour is at the core of it".