The government has been accused of creating a biased panel since two of its three members are outspoken opponents of allowing Canadians to seek medical help to end their lives.
But MacKay, who is not seeking re-election, said Wednesday it's important to remember who holds the decision-making power.
"Ultimately, it is the executive branch of the country that will make these important decisions on legislation that I believe, and this is my view, are necessary to fill what is quite a gap now in our Criminal Code as a result of the Carter decision," MacKay said in Halifax.
MacKay said the panellists will consult with a "broad array of participants" before reporting back to the government in late fall — after the Oct. 19 election. It has been asked to recommend options for how the government should respond to the Supreme Court's ruling last February, which struck down the prohibition on physician-assisted suicide.
"But let's not forget at the end of that process, whoever that justice minister and health minister may be, whatever government may be, those are just recommendations," MacKay said.
The British Columbia Civil Liberties Association has expressed concern that two of the three panellists were federal witnesses opposed to medical aid in dying when the case was before the top court.
The panel’s chairman is Harvey Max Chochinov, the Canada research chair in palliative care at the University of Manitoba.
His co-panellists are University of Ottawa law professor Benoit Pelletier, a former Quebec cabinet minister who is a constitutional expert; and Catherine Frazee, former co-director of Ryerson University’s institute for disability research and education.
Chochinov and Frazee both argued against doctor-assisted dying before Supreme Court.
MacKay denied the panel composition was designed to predetermine an outcome, although he acknowledged that the decision left him personally troubled.
"When the Supreme Court stripped out those two sections of the (criminal) code, it does leave room for quite broad interpretation of an area that I find quite troubling and that is assisted-dying," he said.
"When I say troubling, I say it is something that touches on deeply held beliefs, it touches on an array of issues whether they be faith, whether they be legal, medical, whether they be concerns around persons for disabilities, so it touches on really important issues for Canadians."
The court gave the government one year in which to craft new legislation that would recognize the right of clearly consenting adults who are enduring intolerable physical or mental suffering to seek medical help to end their lives.
MacKay said he personally doesn't think the deadline is "realistic," especially given that a federal election this fall will disrupt the legislative process.
"I think on a subject as far reaching and as serious as this, a government, a future government, a future minister, should take the time to get it right," he said. "That would be my personal view."
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