One of two British Columbia women challenging the federal government's restrictive law on medically assisted dying has been able to end her suffering with the help of a doctor.

But Robyn Moro's case will continue to be part of the constitutional challenge, held up as an example of the torment individuals can be forced to endure due to uncertainty over the law's requirement that a person's natural death must be "reasonably foreseeable."

The 68-year-old suffered constant, excruciating pain from Parkinson's disease but her doctor, Ellen Wiebe, determined last March that she was not eligible for assistance in dying because she was not near death.

"To say no to her was one of the hardest things I've ever done," Wiebe said in an interview.

Wiebe changed her mind last month, based on an Ontario Superior Court ruling in June that sought to ease physicians' fears that they could be prosecuted for murder if they helped a 77-year-old woman, known only as AB, end her life when her natural death was not imminent.

Justice Paul Perell clarified that the ambiguous, reasonably foreseeable death provision does not mean a person's illness must be terminal or that their death must be imminent or likely to occur within a specific time frame.

Based on that ruling and with another doctor's concurrence, Wiebe helped end Moro's suffering on Aug. 31.

Dr. Ellen Wiebe initially said Moro was not eligible for assistance in dying but reversed her decision after an Ontario court ruling. (CBC)

Law unevenly applied, doctor says

Prior to the ruling, Wiebe said all she had to go on was Justice Minister Jody Wilson-Raybould's assertion that Kay Carter — the 89-year-old at the heart of the Supreme Court's landmark decision in 2015 to strike down Canada's prohibition on assisted dying — would have qualified for an assisted death under the new law because of her age.

Using actuarial tables, Wiebe concluded that Carter, who suffered from spinal stenosis, could have lived another five or six years had she not travelled to Switzerland to receive a doctor-assisted death in 2010.

Hence, Wiebe — who has helped more than 80 Canadians end their suffering since the law was adopted just over a year ago — would not assist in the death of anyone, including Moro, whom she estimated had more than five years to live.

However, her calculation changed after the ruling in the case of AB, who suffered from severe osteoarthritis. Based on actuarial tables, Wiebe concluded AB could have lived another 10 years — a length of time she didn't believe Moro could have survived, given the severity of her condition.

Wiebe acknowledged that her approach to deciding if death is reasonably foreseeable is imperfect and that many other doctors have been much more conservative in their interpretation of the law, with some insisting on a time frame of as little as six months. As a result, she said the law is being unevenly applied across the country.

'It is cruel'

Parkinson's is a degenerative disorder of the central nervous system. It caused Moro continual agonizing pain in her legs, acute nausea that resulted in repeated hospitalization and tremours that shook her whole body.

Her condition was exacerbated by the fact that she was allergic to many of the medications normally prescribed for the disease and for pain relief.

"Robyn spent the whole summer suffering terribly," her husband, Len Moro, said in a written statement to The Canadian Press.

"I would hold her in my arms as she begged for the pain to stop, yet I could do nothing to help. This is where the law left us."

In 2015, the Supreme Court of Canada struck down Canada's law against doctor-assisted dying. (CBC)

While it's wrong to deny an assisted death to someone just because they aren't close to a natural death, he added: "It seems just as wrong to be ineligible one day and then eligible the next based solely on an interpretation."

During her final days, he said the lack of certainty about the eligibility criteria caused his wife to fear the government would interfere to stop her from receiving an assisted death. That caused her "a great deal of stress" and prevented her from sharing her decision to end her suffering with everyone close to her.

"Robyn did not trust the Canadian government with her end of life matters. Nor do I," Len Moro said.

"The law is wrong. It is cruel. In Robyn's memory, we carry on the fight."

Moro still part of challenge

Jay Aubrey, counsel for the B.C. Civil Liberties Association, which is spearheading the court challenge, said Moro will remain part of the case, either through her written affidavit or with her husband as a substitute plaintiff.

The BCCLA, which also spearheaded the original court challenge that led to the Supreme Court's Carter decision, launched the latest challenge last year with Julia Lamb as the sole original plaintiff.

Lamb, who is 26 years old and uses a wheelchair for mobility, suffers from spinal muscular atrophy, a degenerative disease that she fears will eventually consign her to years of unbearable suffering, unable to use her hands, breathe without a ventilator or eat without a feeding tube.

Moro was added to the case in May.

The BCCLA contends the law violates suffering individuals' charter rights and is more restrictive than the assisted dying regime envisaged by the Supreme Court in the Carter case. The top court directed that medical assistance in dying should be available to consenting, competent adults with "grievous and irremediable" medical conditions that are causing them enduring suffering that they find intolerable.

Unlike the subsequently drafted law, the court did not stipulate that a person be near death or that they be "in an advanced stage of irreversible decline" from a serious and incurable disease.

Written by Joan Bryden for The Canadian Press