Marc Nadon cannot take his seat on the Supreme Court of Canada, the court's justices said Friday, in an unprecedented move that blocks Prime Minister Stephen Harper's latest appointment to the top court. 

In a six to one decision, a majority of justices on the top court ruled that Nadon doesn't qualify to join them on the court.

Toronto lawyer Rocco Galati had challenged the appointment of Nadon by Prime Minister Stephen Harper. Galati argued he didn't qualify for one of the court's three Quebec seats because he came from the Federal Court and not from a Quebec 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.

Harper referred the question to the court and Nadon stepped aside until the matter could be decided.

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More to come