Quebec argues delivery of health-care services is a provincial jurisdiction and maintains it is on firm legal ground with the landmark bill — the first of its kind in Canada.
Assisted suicide and euthanasia, however, are illegal under Canada's Criminal Code and the federal government has insisted it has no intention of changing that.
"The laws that prohibit euthanasia and assisted suicide exist to protect all Canadians, including those who are potentially the most vulnerable, such as people who are sick or elderly, and people with disabilities," Justice Minister Rob Nicholson said in a statement Wednesday.
He added the Supreme Court had upheld existing laws and Parliament had voted against any changes in 2010.
"This is a sensitive issue for many Canadians, with deeply held beliefs on both sides of the debate," Nicholson said.
It's one of the few times the Quebec government has managed to get a rise out of its federal counterpart since the Parti Quebecois took power last September.
While Premier Pauline Marois has promised to choose her battles in her minority-government status, she vowed during the election campaign she would not be shy about picking fights with Ottawa in seeking gains for Quebec.
She explained the long-term plan was to cite any federal rebuffs as an argument for Quebec separation.
At a news conference Wednesday, provincial Social Services Minister Veronique Hivon, who sponsored the right-to-die bill, said the Quebec government believes it is on solid legal ground.
"It has nothing to do with criminal matters," she said in Quebec City. "It has everything to do with health matters and that's the perspective that is in this bill and we're really confident that we're on solid grounds."
She said Quebec had not received any warnings from the federal government to kill the bill.
"I think they recognize, as we do, a certain flexibility in Quebec in matters of health, as confirmed by legal experts," she said.
Hivon, who is also junior health minister, said the term "physician-assisted dying" was carefully chosen for the legislation and does not constitute a euphemism for euthanasia or assisted suicide.
Udo Schuklenk, a medical ethics expert at Queen's University in Kingston, Ont., praised the Quebec government for its initiative and said its provisions reflected recommendations in a Royal Society of Canada report on end-of-life care to which he contributed in 2011.
However, he said it will likely be years before the legislation is implemented, even if it is passed, because court challenges are inevitable.
"The case that has to be decided here is of course not an assisted-dying case," he said.
"The question here is whether or not a province is entitled to issue regulations and legislation in a domain that the provinces are properly responsible for, in this case health care, if the regulations they want to put in place impinge on the Criminal Code, as clearly this does."
The tabling of the legislation in Quebec City comes five months after a panel of experts concluded that provinces have the legal jurisdiction to legislate in matters of health.
Hivon suggested it is a humanitarian response to a heartbreaking situation.
"There are people in Quebec who suffer and who don't find answers to their suffering at the end of their life and the whole idea behind this bill is to give the answers that are needed for those people," she said.
The bill has three main thrusts — expanding palliative care, setting protocols for doctors sedating suffering patients until they die naturally, and guidelines to help patients who want to end their pain.
Bill 52 says patients themselves would have to repeatedly ask a doctor to end their lives on the basis of unbearable physical or psychological suffering. They would have to be deemed mentally sound at the time of the requests.
Two physicians would have to approve the request, which would have to be made in writing.
The Canadian Medical Association defines euthanasia as knowingly and intentionally performing an act that is intended to end someone's life. It says the act is carried out with compassion and without the intent of personal gain.
The association describes assisted suicide as intentionally giving someone the knowledge or the means — or both — to commit suicide. It defines aid in dying as a generic term that encompasses both euthanasia and physician-assisted suicide.
In an email response to a request for comment, the association reiterated its longstanding policy that it opposes euthanasia and physician-assisted suicide.
It said it will use its annual meeting in Calgary in August to examine such issues as access to palliative care and physician-assisted dying.
Hivon said she's aiming for public hearings on the bill in September.
The legislation follows a landmark March 2012 report that suggested doctors be allowed in exceptional circumstances to help the terminally ill die if that is what the patients want.
It followed divisive public hearings held across the province in 2010 and 2011.
"Now there are specifics of the bill so it's important to hear a certain number of groups and associations," Hivon said, adding she hopes to see a high degree of non-partisan collaboration.
The legislation received mixed reviews.
Claude Leblond, president of the provincial order of social workers and family therapists, said the bill is a major step forward.
"It took women years to get recognition for their fundamental right to terminate an unwanted pregnancy," he said. "When acquired, the right to seek medical aid in dying will be a comparable victory."
He said while only requests by adults will now be considered, the day may come when the wishes of children will also have to be taken into account.
However, the Physicians Alliance for Total Refusal of Euthanasia said flatly in a statement that "killing has no place in health care in Quebec."
"This bill has been developed through a process that is neither just or credible," said the group, adding it expects it will be challenged in the courts.
Paul Saba, spokesman for the Coalition of Physicians for Social Justice, feared abuses in Quebec's already stretched health-care system and predicted no doctor will ever accept ending a patient's life because it violates the Hippocratic oath.
He said he's heartened by the expansion of palliative care and wants to it to go further.
"The government needs to put their money where their mouth is," he said.
Saba said while the government can't provide the best palliative or in-home care in someone's final days, they're basically telling patients "we've got this big needle for you." Patients might opt for it because they fear being a burden on their families or because they're not getting proper pain treatment, he said.
"They call it end-of-life care. That's not care. That's killing a patient because you're not providing them with appropriate care."
Also on HuffPost