The federal government decriminalized attempted suicide in 1972 and the legal right to turn down medical treatment emerged at around the same time, as technological advances in medicine allowed doctors to keep patients alive longer.

In the 1970s, a series of court cases won a mentally competent person the right to refuse medical intervention.

The debate over patient autonomy today centres on issues of active euthanasia and assisted suicide, as patients who live in chronic, intense pain or with a degenerative or terminal illness such as multiple sclerosis, AIDS or Alzheimer's disease fight for the right to choose to die.

Eighty-four per cent of Canadians surveyed in a 2014 poll said they agreed that "a doctor should be able to help someone end their life if the person is a competent adult who is terminally ill, suffering unbearably and repeatedly asks for assistance to die."

The assisted suicide poll was commissioned by Canadian charity Dying with Dignity. It was conducted online by Ipsos, a market research company, which surveyed more than 2,500 Canadians between August 21 and 29, 2014.

An overview of the key events in the assisted dying debate in Canada:

February 6, 2015: The Supreme Court of Canada unanimously overturns a legal ban on doctor-assisted suicide, ruling the law should be amended to allow doctors to help in specific situations.

January 6, 2015:  The Supreme Court of Canada hears an appeal from the B.C. Civil Liberties Association seeking to overturn the legal ban on doctor-assisted dying.  

August 2014: Gillian Bennett, a B.C. woman diagnosed with dementia three years ago, kills herself by ingesting drugs. Before her death, she posted on her blog that she feared she would become a burden on her family and did not want to spend "an indefinite number of years of being a vegetable in a hospital setting." Bennett also hoped to reopen the debate about assisted suicide.

June 2014:  The National Assembly in Quebec passes Bill 52, known as the 'dying with dignity' law, allowing terminally ill patients to have medical aid in dying. The bill follows Europe's lead by extending the law's reach to those experiencing "unbearable suffering," but who may not be within months of dying.

March 2014:  Winnipeg Tory MP Steven Fletcher introduces two private members bills. One allows doctors to help people end their lives under certain restricted circumstances, including the individual must be of "sound mind" with "an illness, a disease or disability (including disability arising from traumatic injury) that causes physical or psychological suffering that is intolerable to that person and that cannot be alleviated by any medical treatment acceptable to that person." The other bill proposes a commission to monitor the system.

September 2013:  The debate regains prominence after Dr. Donald Low, a Toronto microbiologist who helped ease public concern during the 2003 SARS crisis, made a plea for assisted suicide in a posthumous video​.

Steven Fletcher

Conservative MP Steven Fletcher has said it's inevitable that Canada allows physician-assisted suicide. (Adrian Wyld/The Canadian Press)

March 2013:  The B.C. Court of Appea​l, in a split decision, affirms the law against assisted suicide, in a controversial and historic right-to-die case brought on by  ALS patient Gloria Taylor of Kelowna and the B.C. Civil Liberties Association, which vowed to appeal the ruling and did. The Taylor case is one of three that went to the Supreme Court.

October 2012:  Gloria Taylor, the ALS patient who spearheaded the movement to change Canada's right-to-die laws, dies from an infection.

June 2012: B.C. Supreme Court Justice Lynn Smith, in a case that includes ALS patient Gloria Taylor, declares Canada's laws against physician-assisted suicide unconstitutional because they discriminate against the physically disabled. In a 395-page ruling, Smith noted suicide itself is not illegal, and therefore the law against assisted suicide contravenes Section 15 of the Charter, which guarantees equality, because it denies physically disabled people like Taylor the same rights as able-bodied people who can take their own lives. Smith also said the law deprives both people like Taylor and those who try to help them of the right to life and liberty guaranteed under Section 7 of the charter. The federal government appeals the ruling to the B.C. Court of Appeals.

May 2009: MP Francine Lalonde introduces a private member's bill for the second time "to allow a medical practitioner, subject to certain conditions, to aid a person who is experiencing severe physical or mental pain without any prospect of relief or is suffering from a terminal illness to die with dignity once the person has expressed his or her free and informed consent to die."  It does not pass and the MP soon resigns. Lalonde dies of bone cancer in January 2014.

December 2008: A Quebec jury acquits Stéphan Dufour on a single charge of assisted suicide. Dufour had admitted to installing in a closet a rope, chain and dog collar that his uncle, Chantal Maltais, used to kill himself in September 2006. Dufour was the first Canadian ever to stand trial by jury for assisted suicide.

June 2007: Dr. Ramesh Kumar Sharm of Vernon, B.C. is given a conditional sentence of two years less a day and has his physician's licence revoked after prescribing a lethal dose of drugs for a 93-year-old patient.

June 2005:  Francine Lalonde, a Bloc Québecois MP, introduces a private member's bill, C-407 which would permit a medical practitioner or someone assisted by a medical practitioner to aid another person to die if that individual has a terminal illness or is experiencing extreme physical or mental pain and "appears to be lucid" when he/she requests to die. The bill does not pass.

sue rodriguez

in 1992, ALS patient Sue Rodriguez began her fight to overturn the law banning doctor-assisted death in Canada. That culminated in a landmark 1993 Supreme Court of Canada decision dismissing her case. Rodriguez died in 1994.

1998: Maurice​ Généreux becomes the first doctor to be sentenced under the law banning physician-assisted death. The Quebec doctor received a jail term of two years less a day and three years' probation in 1998 for prescribing sleeping pills to two men with AIDS who were depressed but not terminally ill. One of the men survived and later launched a civil suit against Généreux.

February 1994:  Sue Rodriguez, assisted by an unknown doctor, dies in her home in Victoria. MP Svend Robinson witnesses her death.

Sept. 30, 1993: The Supreme Court of Canada, in a 5-4 decision, dismisses the appeal of Sue Rodriguez, who has ALS (a.k.a. Lou Gehrig's disease) and wants a physician to help her die.  The decision includes concerns about potential abuse and the difficulty of creating appropriate safeguards.

December 1992: MP Svend Robinson, the New Democratic Party MP from Burnaby-Kingsway in B.C., introduces a private member's bill, C-385, "to allow for physician-assisted suicide upon the request of a terminally ill person." The closing of Parliament prevents the bill from coming forward for debate.

1992: Sue Rodriguez begins her fight to overturn the law banning doctor-assisted death in Canada.

1991: The Right to Die Society is founded in Canada in Victoria, B.C. to help guide those who need assistance in dying and to lobby for the legalization of assisted suicide.