What mandates "strict construction"?

Question

Assuming there is a class of contracting parties which are allowed unilateral changes to contracts (e.g. landlords, banks, etc.) by law. Does that imply that such a law must be interpreted under "strict construction" or "narrow interpretation"?

It seems like it should be so that the other parties' rights (to negotiate their contract obligations and considerations) are diminished in the least ways possible.

But is that a general legal principle? Is it protected by law or precedent? Or does it depend on each individual jurisdiction?

Answer 1

canada

The principle of strict construction has no role in the interpretation of statutes relating to contract law.

As a starting point, no enactment is to be construed strictly. See the Interpretation Act:

Every enactment is deemed remedial, and shall be given such fair, large and liberal construction and interpretation as best ensures the attainment of its objects.

However, in interpreting penal laws, there remains a limited and exceptional role for strict construction (La Presse inc. v. Quebec, 2023 SCC 22):

a provision is only “ambiguous” ... if its words can reasonably be interpreted in more than one way after due consideration of the context in which they appear and of the purpose of the provision. This is to say that there is a “real” ambiguity — one that calls for the use of external interpretive aids like the principle of strict construction of penal laws ... only if differing readings of the same provision cannot be decisively resolved through the contextual and purposive approach.

Answer 2

australia

No

In interpreting a provision of an Act, the interpretation that would best achieve the purpose or object of the Act (whether or not that purpose or object is expressly stated in the Act) is to be preferred to each other interpretation.

s15AA Acts Interpretation Act 1901.

AFAIK, all states and territories have legislation stating essentially the same thing.