The Supreme Court of Canada is scheduled to hear arguments Monday and Tuesday on whether the federal cabinet exceeded its authority when it banned roughly 1,500 firearm models and variants in May 2020.
The prohibition covered firearms including the AR-15 and Ruger Mini-14.
Subsequent federal measures brought the total to more than 2,500 models and variants the government classifies as assault-style firearms.
At the centre of the case is a limit Parliament placed on cabinet’s power to prohibit firearms by regulation.
Cabinet cannot use that power to prohibit a firearm it considers reasonable for hunting or sport shooting in Canada. The two sides disagree over how cabinet should have made that assessment.
The federal government argues cabinet was entitled to weigh public safety, including the potential for the firearms to increase the severity of mass shootings.
Federal lawyers acknowledge some of the firearms were previously used lawfully for hunting and sport shooting, but say thousands of legal alternatives remain available.
Appellants, including the Canadian Coalition for Firearm Rights, argue the lower courts failed to adequately consider how the firearms were actually used.
They say the regulations disrupted the lives of lawful owners and businesses, and are asking the Supreme Court to determine whether Parliament authorized a ban with those consequences.
The Federal Court dismissed the challenge in 2023, and the Federal Court of Appeal upheld that ruling in 2025.
The appeal court found cabinet could consider public safety when deciding whether the firearms were reasonable for hunting or sporting purposes.
The federal government has extended the amnesty orders covering the 2020, 2024 and 2025 prohibitions. The orders are set to expire 90 days after the Supreme Court issues its decision.