Unlikely alliances and concerns over vulnerable people’s rights have led to fierce debate and ethical uncertainty

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When Kim Leadbeater came top of the ballot of private members’ bills, she did not immediately decide to attempt a generational change in the way the British state handles life and death. But, she says, it was an opportunity that rarely comes for a backbench MP.

The past few months campaigning for her bill to legalise assisted dying have exhausted her. It has been a licence for everyone she meets – in parliament, in the street, everywhere in her life – to tell harrowing stories.