Jemma is walking down a busy road listening to her i-pod nano through her earphones.She steps onto the road without looking and is run over by Mr Button who is driving at 45 mph in a 30 mph zone.Jemma suffers broken bones and is off work for two months.Mr Hussein, an elderly gentleman, is walking along the road and witnesses the accident.Sadly Mr Hussein has a weak heart and dies at the scene.

Discuss the extent of Mr Button's liability in this situation.