Although clips of dash cam captures are often used as entertainment in web and TV programs, they have a big use when it comes to fighting driver bad behaviour on the road, and even in crime investigations.

A problem overseas, less so here because of the ACC scheme, are the deliberate “crash for cash” frauds — basically a car will stop suddenly in front of you causing you to crash into them; then they claim their whiplash injury is your fault. Dash-cam footage should tell the truth.

There have also been cases overseas when automatic-on-start-up dash cams in stolen cars have revealed strong clues about what the criminals did.

You can get a good one for about $100 in America, or equivalent prices here.