Crown lawyer Donnaree Nygard told the B.C. Court of Appeal, which began a week long review of Canada's assisted suicide ban, that patients faced with a traumatic injury or a terminal disease often can't imagine how they'll be able to carry on.
"But many of those people find that in fact they are able to cope and they are able to find enjoyment in life," said Nygard. "They are acting out of a fear of the future."
Nygard's arguments prompted Chief Justice Lance Finch to ask whether life was more than a pulse or electrical activity in the brain.
"It's surely the ability to engage in or appreciate the full range of human experience," he said. "This argument is cast in such negative terms. It's about fear of avoiding suffering or fear of loss of autonomy. But (isn't) life a big positive?"
Last June, the B.C. Supreme Court struck down Canada's ban on assisted suicide, which has been in place since 1892, as unconstitutional. The court ordered Parliament to rewrite the law, but instead the federal government launched an appeal.
The case pits the rights of people to choose the circumstances of their death against the possibility vulnerable individuals could be put at risk if the law were to change.
Nygard said medical advances mean most physical pain can now be controlled and there are also ways of dealing with psychological distress.
Finch asked: "Shouldn't it be up to the individual to decide when that's no longer a life for him or her?"
The case was initially brought by a woman who accompanied her ailing 89-year-old mother to Switzerland in 2010 so the senior could legally end her life.
Since then, more people joined the case, including Gloria Taylor, a terminally ill 63-year-old woman from Kelowna B.C., who was suffering from ALS, or Lou Gehrig's disease. Taylor was granted a constitutional exemption to seek doctor assisted suicide, though she died in October of an infection.
The federal government has warned legalizing assisted suicide could put vulnerable patients at risk, because they could be coerced into ending their lives or decide to do so in moments of fear or weakness.
Nygard said Parliament has weighed the considerations on either side of the divisive debate numerous times.
"And on each occasion, (Parliament) has come to the conclusion that the need to protect individuals in vulnerable circumstances outweighs the interests of those who seek assisted suicide," she said.
Nygard said it should be up to Parliament, not the courts, to decide the emotionally charged issue of assisted suicide.
"The trial judge erred in addressing the case as if she were tasked with deciding what the right answer was, rather than deciding if the Parliament had struck a reasonable and appropriate balance," she said.
She noted a number of governments for Western democracies have had the same debate, and the "vast majority" came to the same conclusion: protecting life must be paramount.
The exceptions are Belgium, the Netherlands, Luxembourg, Oregon, and Washington state, Nygard said.
Similar legislation has been rejected in 24 American state legislatures since 1991, she said. The Scottish Parliament and Australia have also tried making cases for legalization of assisted suicide but were unsuccessful.
The B.C. Supreme Court decision said the law must allow physician-assisted suicide in cases involving patients who are diagnosed with a serious illness or disability and who are experiencing "intolerable'' physical or psychological suffering with no chance of improvement.
"This order is broader than anything that exists anywhere else," Nygard said.
"What is required is an absolute ban."
Before court began, Amy Hasbrouck of the group Toujours Vivant-Not Dead Yet said she opposes legalizing suicide because it can have a discriminatory effect on people with disabilities.
"Society has a public policy to prevent suicides and that policy is a great one — we exercise it for people who are young, who are being bullied, people who are lesbian, gay, transgendered, bisexual and anyone in distress," she said.
"Except for, if a person has a disability and expresses the same suicidal feelings, that person who requests assisted suicide is likely to get it, and we feel that is a discriminatory double standard."
The appeal will be heard over a week, with submissions from several advocacy groups including the Farewell Foundation, which supports doctor assisted suicide, and the Alliance of People with Disabilities, which is against the practice.
Experts on both sides expect the case is headed to the Supreme Court of Canada for a final decision.
Canada's prohibition was last upheld two decades ago when the Sue Rodriguez took her case to the Supreme Court of Canada but lost by a narrow ruling.
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