Five years after Sean Davison was arrested for helping his mother to die, an organisation he founded has won a landmark victory allowing assisted suicide in South Africa.
Auckland-born Dr Davison served five months' home detention in Dunedin in 2011 for giving a lethal dose of morphine to his mother, Dr Pat Davison, to relieve her pain when she was dying of cancer at the age of 85.
Last week, a South African High Court judge ruled that a doctor could legally help another dying cancer patient, Johannesburg lawyer Robin Stransham-Ford, to end his life "either by administration of a lethal agent or by providing the applicant with the necessary legal agent to administer himself".
The judgment, and a similar judgment in the Canadian Supreme Court in February, has forced the issue of euthanasia on to the political agenda of reluctant Parliaments across the English-speaking world.
Terminally ill Wellington brain cancer patient Lecretia Seales, 42, has filed a claim seeking the right for a doctor to help her die. It will be heard in the High Court on May 25. Her lawyer, Dr Andrew Butler, said he would rely on the Canadian and South African cases as precedents.
"Lecretia has been very clear that she thinks it's a topic Parliament should be addressing," he said.
Sean Davison, 52, said the euthanasia issue "never crossed my mind" until his mother's pain forced him to confront it.
His arrest in September 2010, after he published a book about his mother's death, made him an overnight celebrity in South Africa, where he is a professor of microbiology and head of the country's top forensic DNA laboratory.
While on bail, he founded Dignity South Africa to lobby for a law change to allow assisted suicide. In 2012, he co-founded Project Innocence, which uses DNA to exonerate people convicted of crimes they did not commit.
He met his wife, Raine Pen, 43, through ballroom dancing. She migrated from China about 14 years ago and they have two boys, aged 6 and 5, and a 1-year-old girl.
Dr Davison still has family in New Zealand and said his wife would be happy to move here one day.
"I love New Zealand, it's where my heart is," he said. "As the autumn years approach, you kind of want to be where your heart is."
A bill promoted by Peter Brown when he was a New Zealand First MP to allow euthanasia for terminally ill patients was lost by only two votes in 2003, and Dr Davison said he was surprised New Zealand had made no progress on the issue since then.
"It's a basic human right, at the core of our humanity," he said. "This is what New Zealand should be leading the world on."