SCC Explains Terrebonne Election Annulment Over Uncounted Ballot

A divided court splits 6-3 on whether an Elections Canada typo was serious enough to undo a riding decided by one vote A divided Supreme Court of Canada has explained why it annulled Terrebonne’s 2025 federal election from the bench in February. The riding was decided by a single vote and undone by a single ballot that was never counted. The court allowed the appeal on Feb. 13, 2026, at the close of oral argument, vacating the seat that day with reasons to follow. Terrebonne voted again on April 13 and returned Liberal Tatiana Auguste, who had won the annulled election by one vote. This time her margin was roughly 700 votes. The reasons in Sinclair-Desgagné v. Canada (Chief Electoral Officer) , released on Sept. 18, split the court 6-3. The case originated with an Elections Canada worker preparing address labels for mail-in ballot return envelopes. He typed the wrong final three characters of the polling station’s postal code. The worker noticed the error on April 6, three weeks before the vote. He corrected the labels on the kits still in the office and destroyed the defective ones that had not gone out. But he did not tell his supervisor, nor did he try to contact the electors – at least 40 by his own estimate – whose mismarked envelopes had already been mailed. One of those envelopes, addressed to Emmanuelle Bossé, was returned by Canada Post with the label "moved / unknown." Her ballot was never counted. Sinclair-Desgagné sought an annulment from a Quebec Superior Court judge, who dismissed her application, holding that an honest clerical slip without dishonest or malicious intent was not an "irregularity" under the Canada Elections Act. The court added that it would not have annulled the election in any event. Using special provisions in the Act that grant a right of appeal directly to the Supreme Court within eight days, Sinclair-Desgagné bypassed the Quebec Court of Appeal and went straight to Ottawa. Justice Mahmud Jamal, for the majority, ruled that an irregularity can include a serious administrative error that is honest and unintentional and that breaches no statutory provision; the question is whether the error could undermine a voter’s franchise. Here, Elections Canada caused the error, knew about it for three weeks, had the ability and the responsibility to fix it, and did nothing. With one affected ballot against a one-vote margin, the result could not stand. The Superior Court had reasoned that counting Bossé’s ballot would have produced a tie. That was itself an error, the majority said: ballot secrecy precludes any investigation into how a voter actually marked her ballot, and that bar applies at every step of the analysis, not only when a court decides whether to annul. Arthur Hamilton, in Dentons Canada LLP’s litigation and dispute resolution group in Toronto, says the split decision exposes a fault line in how the public views the court’s role regarding election results. "The majority and the dissent have competing instincts about what most people feel about courts undoing elections. Which one is persuasive being largely in the eye of the beholder." The majority’s view holds that a voter who did everything asked of her should not lose her vote to the state’s mistake and failure to correct it. The dissent reasons that elections should not be reopened over a typo. The dissent, written jointly by Justices Andromache Karakatsanis and Sheilah Martin with Justice Mary Moreau concurring, anchors its reasoning in the Canada Elections Act. The statute provides that an elector who votes by special ballot "shall ensure" the ballot is received on time and has the "sole responsibility" to do so. Nothing in that text, the minority concluded, limits the elector’s responsibility when Elections Canada or anyone else makes an error. Bossé had a tracking number. She did not use it, nor did she vote in person. The disse