Supreme Court confirms that conservation zoning can be de facto expropriation

October 6, 2022 | Adina Georgescu

On September 29, 2022, the Supreme Court of Canada dismissed the application for leave to appeal filed by the City of Mascouche (the “City”) in Ville de Mascouche v. Dupras, 2022 CanLII 88678 (SCC).

This confirms the Québec Court of Appeal’s decision in Ville de Mascouche c. Dupras, 2022 QCCA 350. The City of Mascouche is thus required to pay damages to Ginette Dupras for de facto expropriation after a new municipal by-law rezoned her lot from 70% residential to 100% conservation use. Her lot, which was valued at several million dollars under residential zoning, lost its development potential under conservation zoning.

In 2016, Ms. Dupras sued the City for de facto expropriation. The Superior Court of Québec ruled in her favour and condemned the City to pay damages. The decision was appealed. The Québec Court of Appeal found that there was de facto expropriation even though the City’s zoning by-law was valid. It ruled in Ms. Dupras’s favour and referred the case back to the Superior Court to increase the damages Ms. Dupras was entitled to.

The City then filed an application for leave to appeal this decision with the Supreme Court of Canada. The Supreme Court dismissed this application on September 29, 2022, confirming the Court of Appeal decision and setting an important precedent on de facto expropriation in Quebec.

This is a victory for land owners affected by conservation zoning. Municipalities, however, see it as a step backward for the protection of natural spaces and have appealed for an urgent change to the legislative and regulatory framework so that they can continue to protect their natural spaces.


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