Nadon, a 64-year-old former Federal Court of Appeal judge, was appointed to represent Quebec in the nine-person Supreme Court in October. However, Nadon almost immediately stepped aside because of a legal challenge about his qualifications.
This unprecedented event came about because a Toronto lawyer, Rocco Galati, formally challenged Nadon's appointment on the grounds that it violates the rules about selecting Quebec judges for the top court.
Galati, better known for specializing in terrorism cases, contended that because Nadon was a Federal Court judge he is not qualified to be one of the constitutionally mandated three Quebec judges on the land's highest court. Quebec judges are a special category because of the province's unique civil legal code, different from the common-law code in the rest of the country.
In response to Galati's challenge, the federal government submitted a reference to the Supreme Court about Nadon's appointment.
Galati was given intervenor status, as were Ontario and Quebec and the Toronto-based Centre for Constitutional Rights.
1. What does the government want from the Supreme Court?
The federal government is asking the Supreme Court to answer two questions. The first is simply whether a judge from the Federal Court, a national trial court dealing with issues in the federal domain, can represent Quebec.
The second is whether the federal government has the power to amend the selection process of a Supreme Court judge. It tried to do just this when it inserted two clauses in its omnibus budget bill in 2013. Odd as it may appear to be in a bill called the Economic Action Plan, clauses 471 and 472 are what the government calls clarifying amendments to the Supreme Court Act.
For instance, one clause specifies that a candidate who ''at any time" was a lawyer or judge with 10 years' experience working with Quebec's civil code should qualify for appointment as a Quebec representative to the top court.
Some legal experts argue, as does Galati, that a Quebec candidate must be a current lawyer or judge in Quebec so that he or she is up to date with Quebec's unique legal system, a requirement that would exclude former Quebec lawyer Nadon, who was appointed to the Federal Court in 1993 and has been living in Ottawa.
2. What's at stake?
"If the Supreme Court rules against him [Nadon] it will be highly embarrassing for the prime minister," said Adam Dodek, a law professor at the University of Ottawa and former Supreme Court clerk.
It could also be embarrassing for Nadon, whose merits as a judge are under scrutiny. Nadon specializes in maritime law, rarely a factor in Supreme Court cases, and he was semi-retired, perhaps a liability considering the top court's punishing workload.
"He's a very accomplished person," Bruce Ryder, a law professor at Toronto's Osgoode Hall and constitutional expert, said in a phone interview. But, he added, "There are better qualified people, particularly on the Quebec Court of Appeal."
Other experts predict dire consequences for the Supreme Court itself if the way is paved for Nadon's appointment to become permanent.
Paul Daly, a professor from the University of Montreal, has written that if Parliament is permitted to make such "sweeping changes" to the nature of the institution, "it could pack the Supreme Court of Canada with sympathetic jurists."
Daly says "it could do away with the requirement that appointees to the court be lawyers." The highest court could even be "abolished altogether," he says.
3. How esoteric can the argument become?
Galati is arguing about the meaning of "is" and "has been" as the words appear in the Supreme Court Act. "Has been," argues Galati, is the continuous present tense, meaning a Quebec candidate must be a current Quebec judge or current Quebec lawyer. The federal government argues that "has been" in this case is the past tense.
4. How did it get to this point?
Some argue not enough time or thought went into Nadon's appointment.
"If there's a problem with the appointment, that should have been discovered before or during the vetting, Dodek said, pointing out that only 72 hours went by between the announcement about Nadon's nomination and his appointment to the Supreme Court bench.
The vetting process, which was conducted by a committee of MPs, was "too narrow, too shallow and it was far too quick," he said.
5. What does it reveal about the process of selecting judges?
Ryder thinks the hearing will finally "shine a light" on the process of selecting judges to the top court, a practice he finds "highly problematic." Judges are appointed by the Governor General on the advice of the prime minister.
"The prime minister, who in a number of ways has not always shown an affection for the charter or the rule of law," Ryder said, is appointing the very judges who have to hold him accountable to both.
6. How long will it take?
Wednesday's hearing is likely to last most of the day. It is possible the court could then immediately issue a ruling from the bench, since the holdup on Nadon causes problems for the court if it only has eight judges to call on.
Others think the issue is so precedent-setting and complex that the court may not rule until the spring or early summer.
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