This article will attempt to shed light on the application of the theory of promissory estoppel in public law when a discretionary power of a public authority is involved. Note that promissory estoppel is essentially the public law principle that a promise is legally enforceable.
In Immeubles Jacques Robitaille Inc. v City of Québec1, the Supreme Court of Canada confirmed that promissory estoppel compels a public authority to fulfill a promise made to a citizen. In this same judgment, the Supreme Court states the criteria for the application of promissory estoppel in public law:
(1) The existence of a clear and unequivocal promise from a public authority, which promise is contrary to neither the public interest nor the law; and
(2) A citizen’s actions predicated on this promise.
Moreover, the public authority’s promise can be inferred from the conduct and statements of the involved parties and the circumstances of the case, as the Supreme Court of Canada pointed out in Maracle v Travellers Indemnity Co. of Canada2.
In Corporation d’hébergement du Québec3, the Superior Court of Québec also recognized that promissory estoppel was applicable to municipalities, and that a promise could be inferred from not only a resolution duly adopted by the council, but also from statements made by a representative of the decision-making body.
More recently, in Corporation d’investissement Montarville4, a case I pleaded with my colleague Jean-Daniel Lamy, the Superior Court of Québec confirmed the application of these principles and, referring explicitly to promissory estoppel, ordered the City of St-Bruno-de-Montarville to allow the plaintiff access to the municipal infrastructure required to develop its building for multiresidential purposes:
“ For the Court, the City’s resolutions in 1981 and 2005, as well as the representations made until 2013, had there been no contractual commitment, would have constituted a clear and unequivocal promise made to CIM on the basis of which it acted and performed several acts, these representations specifically aimed at inciting it to perform certain acts in the wake of the initial promise made in 1981 to ensure the accessibility of an accepted project.
 The City having, by its representations and promises, led the CIM to commit and act on them, the new elected officials no longer had the latitude to reverse these representations and promises.”
This decision is one of the very few rendered in Quebec allowing a developer to force a municipality to extend a street and municipal services in the absence of a duly signed memorandum of understanding.
1.  1 S.C.R. 784 2.  2 S.C.R. 50 3. 2011 QCCS 2573 4. 2020 QCCS 228