★★★Yet while there are plenty of motorists who are convinced dash cams really do make life easier in the event of an accident, others believe they are the thin end of a disturbing wedge, in which insurance companies and law-enforcement agencies will be able to gather and collect data about yet another aspect of our private lives.
It ruled all that out, and entirely proved my innocence.'Better still, when it came to dealing with the normally time-consuming and frustrating business of making an insurance claim, the footage was equally useful as it comprehensively proved the Astra driver was at fault.
Those of us unlucky enough to have spent weeks, if not months, wrangling with insurance companies in the wake of an accident will look upon Mr Pettifor's experience with an envious eye.
Typically, these more complex dash cams are connected to a vehicle's electricity supply via the fusebox, while the simpler versions are powered through a cable that runs to the 12-volt socket. The cheapest models can be as little as £30, with the priciest running to some £300.
However, it is not necessary to spend much more than about £150.
But in this instance they were armed with a powerful piece of evidence that showed exactly where the blame lay – video footage from Mr Pettifor's dashboard camera, or 'dash cam'.'The police saw it right there and then and they instantly knew it was not my fault,' says Mr Pettifor.