Fully autonomous cars may never be allowed on many public roads, according to BMW’s special representative to the UK, Ian Robertson.

Speaking at the Society of Motor Manufacturers and Traders (SMMT) Summit, Robertson highlighted BMW’s leading role in developing self-driving systems but conceded that it may never be morally acceptable to leave the decision for unavoidable accidents to a machine. “Imagine a scenario where the car has to decide between hitting one person or the other — to choose whether to cause this death or that death,” he said. “What’s it going to do? Access the diary of one and ascertain they are terminally ill and so should be hit? I don’t think that situation will ever be allowed.”

BMW already has more than 40 vehicles testing on public roads running on 660-mile (1000km) journeys routinely. However, Robertson revealed that, while the majority of the trips are completed without problems, the engineer on board has to intervene on average three times.

“That’s good, but we are working in a scenario where it has to be perfect,” he said. “If we are working towards a ‘brain off’ scenario, where perhaps we expect travellers to even sit in the back of the car and relax, then that clearly isn’t possible today, despite what some might tell you.

“Then there is the overarching consideration of the regulators that we need to consider. In the UK, the government is encouraging autonomous testing — even if some of its fundamentals go against the Highway Code, the fabric of our laws. They know we are in a race to take leadership and that opening up to testing could have significant benefits.

“But I believe that in the long term, the regulators will step in and set boundaries about how far we can go. It might be to allow it only on motorways, as they are the most controlled environments.

Or perhaps they’d essentially ‘rope off’ parts of cities to allow autonomous cars into controlled areas, where the consequences for pedestrians are controlled.”

While still BMW’s sales and marketing chief last year, Robertson stated that he could never see a scenario where the firm made cars without steering wheels.

He instead suggested that the occupants would always want the option of choosing to drive themselves.