Expressing Permission, Powers or Rights


Provisions granting a permission, power or right to do something that is otherwise prohibited or for which authority does not otherwise exist are to be drafted using the auxiliary verb “may”.

Legislative counsel should avoid the use of  “may not” and “no person may” to limit or deny a permission, power or right and seek an alternative using phrases such as


Permission, powers or rights

Section 11 of the Interpretation Act states that “may” is to be construed as “permissive”. Accordingly, it is used for provisions that permit people to do things that they would not otherwise be allowed or able to do. For example, it is used in the following ways:

A grant of powers generally includes the discretion to decide whether the powers should be exercised. However, in certain contexts, there may be a duty to exercise the power despite the use of “may”. As Ruth Sullivan states:

There are many cases in which the courts have found the power conferred by “may” to be coupled with a duty once all the conditions for the exercise of the power have been met…The duty if it arises, is inferred from the purpose and scheme of the Act or from other contextual factors.[1]

Limiting or denying a permission, power or right

There are several ways to draft a limitation or denial of a permission, power or right:

Traditionally, the negation of “may” (no person may; X may not) has been used in legislative texts to limit or deny a permission, power or right. This use was endorsed by Elmer Driedger:

Since Every person may isa universal grant of permission, power or right, the opposite No person may is a withdrawal or denial of permission, power or right. This form is apt where the legislature has somewhere granted permission, power or right, and it is now intended to make an exception.[2]

However, as Driedger warns, the word may can be troublesome:

There are situations where may is used and it is not clear whether the legislature has merely made an exception to a grant or has issued an injunction, and there would be doubt whether or not penal consequences follow the doing of what is said not to be permitted.[3]