Cushing v Dupuy is a Canadian constitutional law case decided by the Judicial Committee of the Privy Council in 1880, at that time the highest court of appeal for the British Empire, including Canada.

The question posed to the lower courts, which attracted much discussion in their deliberations, was whether the transaction was a valid sale within the meaning of arts.

It was a simulated sale, intended to create a security on the assets and thus avoid the delivery of possession that was essential for the validity of a pledge under arts.

The Judicial Committee granted special leave on 27 November 1878, while reserving to Dupuy the power to question whether jurisdiction existed to hear the appeal.

On the first point, he ruled that the Queen's Bench had correctly held that it did not have the power to grant leave to appeal, but that the Judicial Committee still retained jurisdiction under the royal prerogative.

[1]: 415 On the second point, Sir Montague Smith held that the effect of the federal provision was to extinguish any appeals under the provincial law in relation to the Insolvent Act of 1875.

He concluded that the Quebec Queen's Bench had correctly held that they did not have the power to grant leave to appeal to the Judicial Committee in matters under the Insolvent Act of 1875.

He reviewed the circumstances of the transaction and found that in form, it was a sale with an immediate lease-back to the insolvent company, who then "...were able to retain the plant and carry on their business as usual."

He stated that the Judicial Committee agreed with the conclusion of Chief Justice Dorion and the majority in the Queen's Bench that whatever the nature of the transaction, it was not a bona fide sale.

1027 of the Civil Code, has since been overtaken by subsequent legal developments in Quebec law, including the rejection of Dorion CJ's contention that creditors are entitled to property remaining in the possession of their debtor as against a third party to whom it has been sold in a bona fide transaction.

[10] While Cushing was notable within Canada for being one of the foundation cases for the doctrine of ancillary powers in Canadian constitutional law, it has also been noteworthy across the Commonwealth for the more general propositions relating to: Following the abolition of Canadian appeals to the Judicial Committee of the Privy Council in late 1949, the Minister of Justice and Attorney General of Canada directed the Department of Justice to prepare a compilation of all constitutional cases decided by the Judicial Committee of the Privy Council on the construction and interpretation of the British North America Act, 1867 (now the Constitution Act, 1867), for the assistance of the Canadian Bench and Bar.