19/08/2014 11:12 BST | Updated 19/08/2014 11:59 BST

Google's Self-Driving Cars 'Programmed To Break The Speed Limit'

Google has admitted that its self-driving cars are designed to intentionally break the speed limit by up to 10 miles-per-hour.

Project lead engineer Dmitri Dolgov told Reuters that the decision was a 'safety feature'. because it can be dangerous to drive slowly on a fast road when everyone else is breaking the limit.

Google's cars are already in testing on US roads, and are designed to operate almost entirely without input from human drivers. The UK will allow the vehicles on the roads from 2015, again in limited tests.

google self driving car

It is expected that new regulations and changes to the UK Highway Code will be needed before driverless cars can be used fully on the roads.

But the concept has thrown up a number of conceptual and safety challenges - including how to account for real-world driving conditions.

Photo gallery See Gallery

"Thousands and thousands of people are killed in car accidents every year," said Dolgov to Reuters, in relation to the "speeding", er, feature. The point is that on a motorway or highway, cars which drive much slower than those around them are at more risk than those breaking the arbitrary speed limit.

The current cars undergoing tests in the US are essentially normal vehicles, but with a large cylinder of sensors and lasers on the roof, and various other tech around the edge of the car.

But Google has also announced a separate line of electric self-driving cars it intends to build which will be limited to 25mph - presumably ruling it out of breaking the law in most circumstances.

Meanwhile a separate but related recent debate focused on whether self-driving cars should be programmed to protect the occupant at all costs, or whether they should prioritise greater numbers of pedestrians outside the vehicle... IE whether your Google car should be programmed to kill you.