His sister Kerry Bromson didn't know when it would be.

She knew he was associated with Doctor Philip Nitschke who founded Exit International, an organisation that supports a person's right to determine the time and manner of their passing, but that was all. Mr Bromson, 66, suffered from carcinoid tumours, a rare and terminal form of bone cancer.

Every organ in his body was functional, but his skeletal body had collapsed, which caused him extreme amounts of pain.

Despite his illness, he ran for the South Australian senate as a candidate for the Voluntary Euthanasia Party (VEP), a political party that supports a request by a terminally ill person for medical assistance to end his or her life painlessly and peacefully.

Mr Bromson ended his life on July 27, 2014, using drugs that had been tested at the Exit International laboratory in Adelaide.

"It wasn't until after he passed that we found out what he had used," Ms Bromson said.

"What was important to us was that we were with him when he passed away - we were able to say goodbye.

"Max's death was one of the most peaceful things you could ever see."

Because Ms Bromson and other members of the family were with Mr Bromson when he took his life, they are part of a coroner's inquiry with results expected in July.

Ms Bromson, who lives in Bowral, became the Australia-wide convenor of the VEP after her brother's death and said she was sure the reason her brother continued his life for as long as he did was because he knew he had a choice.

"It [voluntary euthanasia] is a personal choice," she said.

"Your family cannot make that choice.

"It's one that you have to make."

The VEP wants a system put in place in Australia modeled the Oregon, USA, or Swiss system where two doctors have to agree the patient genuinely wants to end their life.

"Neither system has evidence of it being abused," Ms Bromson said.

"If voluntary euthanasia was legalised, a doctor has the right to follow the directive you made when you were of sound mind.

"My brother would have stayed alive longer if the medication could have been administered by someone else."

The VEP has 15 candidates contesting seats in the Upper House at the NSW State Election 2015.