30 October 2002: The use of hidden speed cameras has shown 'significant' drops in speeds, crashes and casualties in trials in New Zealand.

After a two-year study, comparing 'hidden' systems with 'signposted' cameras, the researchers at the Land Transport Safety Authority in Wellington also found that the falls were sustained, compared to motorist attitudes in visible camera areas, where driving habits reverted back to what they had been after a period of time.

The hidden camera programme, used in 100 km/h speed limit areas, also resulted in a fourfold increase in ticketing.