A legal challenge to Quebec’s secularism law, known as Bill 21, will be heard at the Supreme Court of Canada beginning Monday, and legal experts say whatever the eventual ruling, it will have a profound effect on constitutional law in Canada.

The highly anticipated high court challenge to Bill 21 has been years in the making, but legal debate is likely to focus primarily on Section 33 of the Canadian Charter of Rights and Freedoms, the provision known as the “notwithstanding clause,” which shields legislation from most court challenges over violations of fundamental rights.

François Legault’s Coalition Avenir Québec government pre-emptively invoked the provision into the law passed in June 2019.

The Quebec law, known as Act respecting the laicity of the state, sets out the principles of secularism in the province. Among its most controversial measures is the prohibition of civil servants who are considered in positions of power — such as police officers, teachers and judges — from wearing religious symbols at work.

“What lies at the heart of the challenge before the Supreme Court is far less the act on state secularism than the criteria for suspending the application of human rights and freedoms,” said Louis-Philippe Lampron, a professor at the Université Laval’s School of Law.

“That’s why the upcoming Supreme Court decision will be a true earthquake in constitutional law, no matter which way the Supreme Court rules.”

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