A 43 year-old woman lost control of her Mercedes as she drove at around 40mph on a 60mph carriageway, and ploughed into an oncoming car on the opposite side of the road.

The driver she hit had to be cut from her vehicle by firefighters and put on board an air ambulance, but she died from a heart attack before the helicopter could take off.

The accused was using a legal hands-free kit, but prosecutors claim the call distracted her enough to justify a dangerous driving charge. Driving while using a hand-held mobile phone was banned in Britain in 2003, but Bluetooth technology and devices with headphones and speakers are still allowed.

However, according to the Department for Transport, hands-free phones can still be considered a distraction and drivers risk legal action if they drive erratically whilst using one.