Marc Nadon finds out Friday whether his tenure as a member of the Supreme Court of Canada will come to an end before he hears a single case.

If that isn't precedent-setting enough, Nadon will still make history as the first member of the country's highest court who's there because his peers decided he was entitled to join them.

It's an extraordinary situation with far-reaching implications for the court itself, for Prime Minister Stephen Harper and maybe even for Quebec's place in Canada.

For Nadon, a former Federal Court judge, it's more than a little awkward to be the subject of a court case rather than the one interpreting the law.

But for Stephen Harper, the risks are twofold. One is the potential embarrassment of a finding that your hand-picked choice doesn't meet the requirements for judges appointed from Quebec.

The other is that, if you do win and the court decides in Nadon's favour, you may be giving support to the separatist side in the midst of a closely fought Quebec election.

Harper has never been averse to risks, and more often than not these days his calculations have little to do with the impact in Quebec, where the Conservatives hold just a handful of seats.

But rekindling federal-provincial squabbling at this juncture ranks as one of the more questionable tactical decisions he could make.

Nadon's qualifications

For those who may have forgotten, the controversy began when Harper tapped Nadon last fall to replace retiring Supreme Court Justice Morris Fish.

It marked the first time that a prime minister appointed a judge for one of the three Quebec seats on the Supreme Court who was not a superior court judge in the province, or an active member of the Quebec bar.

Within weeks Nadon's qualifications were challenged, first by Toronto lawyer Rocco Galati and then by Pauline Marois's Parti Quebecois government.

Harper then upped the legal ante, by formally referring the case to the Supreme Court and by introducing an amendment to the Supreme Court Act to change the rules should the high court find Nadon doesn't meet the existing criteria.

As a tactical decision, this was a doozy. In effect, Harper asked the Supreme Court for its opinion while serving notice that he would change the rules if he didn't like the answer.

Galati, who stated his case at the January hearing, accused the Conservatives of trying to stack the court with ''judges who are more friendly to their point of view.''

Other legal experts were somewhat more circumspect.

"No matter what is decided Friday this is a very sad chapter for the Supreme Court,'' says University of Ottawa law professor Carissima Mathen. "It puts the court in the difficult position of having to decide the qualifications of one of its own.''

A judicial conservative

Why is the Harper government so determined to appoint Nadon? At the time, government sources called him a judicial conservative from a province known for activist judges (no doubt fuelling Galati's claim).

They and others pointed to his dissenting opinion in the Federal Court of Appeal ruling that Canada was required to repatriate Omar Khadr from the U.S. prison in Guantanamo Bay.

They also noted Nadon rejected the bid by Green Party Leader Elizabeth May to be included in the televised leaders' debate in the 2011 election.

What those government officials and many others didn't address at the time were the constitutional underpinnings of the law that sets out the three Quebec seats on the Supreme Court, requirements that were designed to guarantee expertise in cases arising under the province's Civil Code.

The Conservatives took the view, and federal lawyers argued, that a lawyer is eligible if he or she has 10 years' experience practicing law in Quebec — a criterion Nadon meets even though he hasn't been a member of the provincial bar for more than two decades.

CANADA-POLITICS/QUEBEC

Parti Quebecois Leader Pauline Marois, after introducing new recruit, media mogul Pierre Karl Peladeau (rear right), has put sovereignty back on the front burner. (REUTERS)

But the political stakes quickly became high.

"It's an important case because it will tell us something about the way the distinct character of Quebec is protected by the Constitution,'' said University of Montreal law professor Paul Daly.

The Quebec government agreed. It argued Ottawa can't unilaterally change how judges from the province are chosen.

The province and others also raised the prospect that any change to the composition of the court requires a constitutional amendment.

Legal limbo

Those are the more abstract legal arguments in a case that has thrust the court into the centre of a politically-charged situation, especially in Quebec where sovereignty is once again at issue in the provincial election campaign.

If the government's position is upheld, it would also allow the prime minister to reach into the Federal Court again to replace another Supreme Court justice, Quebec's Louis LeBel, who is to retire later this year.

Many legal experts say this case is almost certain to renew calls for a more transparent process for appointing judges, and for a more thorough review than the brief appearances appointees now make before a parliamentary committee, where MPs are allowed to ask only the most general of questions.

Nadon went through just such a review last fall when he introduced himself as a former hockey player of some skill, but where his judicial thinking received little in the way of serious scrutiny.

Since then, Nadon has remained in legal limbo. A Supreme Court justice in name, but not in practice.

Since October he hasn't sat on a single hearing, or worked in any way with his fellow judges. He hasn't even been allowed into the building.

On Friday, he and the rest of the country will learn if he can finally get into the game.