The Canadian government has the legal authority to set Chinese telecommunications executive Meng Wanzhou free immediately, and is wrongly claiming otherwise after being embarrassed over revelations of political interference in the prosecution of SNC-Lavalin Group Inc. last year, a former Liberal justice minister and a former Supreme Court judge say.

The result is that two Canadians’ liberty, health and perhaps their lives are at risk in China, without Canada debating the legitimate option of relenting to Chinese pressure and freeing Ms. Meng, Allan Rock and Louise Arbour say.

Canada needs “a full debate based on a legitimate foundation of facts, rather than an incantation of rubrics, like ‘rule of law’ and the ‘independence of the courts’ and the ‘sanctity of the judiciary,‘” Mr. Rock, who was justice minister and attorney-general from 1993 to 1997, said in an interview.

Prime Minister Justin Trudeau and Justice Minister David Lametti say the court process must be allowed to unfold so as not to compromise the independence of Mr. Lametti’s ultimate decision on whether Ms. Meng should be surrendered to the United States for prosecution. In extradition cases, the justice minister first delegates to his officials a decision on whether a case can proceed; a court then holds hearings and decides whether the legal tests for extraditing a suspect have been met; and then the justice minister decides whether to surrender the suspect for trial. The Meng case is partway through the court hearings, and Mr. Rock says it may be 2024 before a judge rules.

Rachel Rappaport, a spokeswoman for Mr. Lametti, said the government’s position is firm. “As this case remains before the courts, and the minister has a direct role in extradition proceedings, it would not be appropriate for us to comment. This has been our position from the beginning.”

Mr. Rock, Ms. Arbour and Vina Nadjibulla sought a legal opinion from Brian Greenspan, a Toronto lawyer with decades of experience in extradition cases, on Mr. Lametti’s authority to withdraw the case. Ms. Nadjibulla is the spouse of Michael Kovrig, one of two Canadians (the other is Michael Spavor) who have been incarcerated for 561 days in China in apparent reprisal for Canada’s arrest of Ms. Meng on Dec. 1, 2018, after the United States requested her extradition on fraud charges related to U.S. sanctions against Iran. Ms. Meng is the chief financial officer of Huawei Technologies Co. Ltd.

Mr. Greenspan wrote a 10-page opinion saying that the Extradition Act has clearly spelled out since 1999 that the justice minister “may at any time withdraw” the government’s support from an extradition case, which triggers a court-ordered release of the extradition subject. (Ms. Meng is free on $10-million bail and living in a Vancouver mansion.) His opinion does not expressly mention SNC-Lavalin, but Mr. Greenspan said in an interview that he had that episode in mind as he set out in detail how the Extradition Act operates differently than a prosecution. Mr. Lametti’s office received the opinion on May 22 and has not responded, Mr. Rock said.

In the SNC-Lavalin affair, first reported by The Globe and Mail in February, 2019, members of the Prime Minister’s Office and other senior officials pressed Jody Wilson-Raybould when she was justice minister and attorney-general to allow a deferred prosecution for the international engineering giant, sparing it from a possible conviction in connection with its business dealings in Libya. The key issue was the independence of the attorney-general from political pressure.

In Canada, one person holds the job of both attorney-general and justice minister. But the Extradition Act, Mr. Greenspan told The Globe, delineates the roles of each. The attorney-general acts on behalf of the requesting country, in this case the United States, in court; and the justice minister decides on Canada’s overall interests, which can include a consideration of international relations and political concerns.

Mr. Rock said that the Canadian government made missteps in the SNC-Lavalin affair, but that the lesson of that episode is playing out wrongly, and to the detriment of Mr. Kovrig and Mr. Spavor, both of whom China charged last week with espionage.

“That was a traumatizing event” for the government, Mr. Rock said of the SNC-Lavalin episode. “My concern is, once bitten, twice shy. In SNC, they shouldn’t have and they did. Here they can and they should, but they won’t. Because they think they can’t, and they’re wrong.”

Ms. Arbour said that she cannot understand the Canadian government’s claim that Mr. Lametti lacks the authority to free Ms. Meng right now, because the law is clear “on its face.” The government is “confused again, but the other way around, about the role of the minister of justice and the attorney-general. The dominant role clearly is of the minister of justice, not the attorney-general, who has a small, very visible, very public part to play – that’s the tail that shouldn’t be wagging the dog.”

Ms. Rappaport declined to comment on whether the government was seeking to apply a lesson learned in the SNC-Lavalin episode.

Both Mr. Rock and Ms. Arbour leave little doubt where they stand in the debate they wish to kick-start over whether Mr. Lametti should withdraw the extradition case.

“When there are lives at stake, you need to just wonder whether an abstract reassertion of values is morally the right thing to do,” said Ms. Arbour, who is a former international war-crimes prosecutor, a former United Nations’ high commissioner for human rights and a former president of the International Crisis Group (ICG). Mr. Kovrig is an employee of the ICG; he was also a staff member at Canada’s UN mission when Mr. Rock was ambassador to the UN.

Mr. Rock said that Canada needs to put its national interest first, and not be concerned about being seen to give in to the bullying of China’s hostage diplomacy, or on the other hand, running afoul of U.S. President Donald Trump by refusing to surrender Ms. Meng. “The very people who tell me we shouldn’t give in to bullies are telling me we better be careful not to do this or the bully [Mr. Trump] will come after us.”

Both said that Canada made a higher-stakes decision under Liberal prime minister Jean Chrétien not to join the U.S.-led war in Iraq, “and you know what? They got over it,” Ms. Arbour said.

Ms. Nadjibulla said she has tried to raise the extradition issue with Mr. Lametti, but was unable to get a response.

She put forward the possibility of stopping the extradition with Mr. Trudeau in June, 2019, the last time she spoke to him about her husband’s plight.

“My plea at the time was the same as it is right now, which is Michael is a Canadian citizen and I hope the Canadian government will explore all options that are available to it to bring him home,” she said.

Ms. Nadjibulla said the legal option took months of serious research and she urged the government to give it proper consideration.

“This is not a situation if the political minister, the minister of justice, were to exercise his authority under the act that would in any way jeopardize the rule of law or the independence of the judiciary,” she said. “We can stop this extradition process if we decide that is in the national interest of Canada and that would serve the interests of Canadian citizens and would save the lives of Canadian citizens.”

The Globe and Mail, June 22, 2020