A lawyer for Tony Nicklinson said he contracted pneumonia and went rapidly downhill after the High Court's decision last week.
Mr Nicklinson told his lawyer that he was "totally devastated."
He died with his family beside him this morning.
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Bristol Mayor George Ferguson has been accused of a "nasty personal attack" in a row over how the city's Green Capital cash was spent.
Bristol Mayor George Ferguson says there will be "further breakdown" of how the city's Green Capital cash was spent.