LGST 551
Introduction to Legislative Drafting (OCW)


LGST 551
Introduction to Legislative Drafting (OCW)

Study Materials

Module 2: Section 3

How do we choose the appropriate auxiliary?

The choice of auxiliary is dictated by the nature of action to be ascribed to the subject. Different auxiliaries prescribe different responses from the subject, and therefore have different impacts. Accordingly, different auxiliaries may be needed to provide for the following:

  • a command (including a prohibition)
  • a power or permission
  • a competence
  • a right
  • a qualification or disqualification
  • a liability
  • a privilege
  • a direction.

Each of these is discussed in turn below.


If the sentence is to require the subject to act or not to act, with some adverse legal consequence for failure, the predicate must create an unqualified duty. Legislative counsel have conventionally used “shall” for this purpose. However, some jurisdictions have discontinued the use of “shall” for this purpose, largely because of the ambiguity that has developed in this term. “Must” is now frequently (although not always) uses as an alternative.

  • “Shall” or “Must”?

    Driedger has argued that “shall” creates a duty while “must” merely asserts the existence of a duty. However, he concedes that a provision using “must” would almost certainly be construed by a court as the source of the obligation. For that reason, he advocated using “must” only if no penal consequences follow on a breach of the duty.

Example 31

Driedger gives the following as an example of where "must" might be suitable:

An agreement must contain the prescribed particulars.

These duties are sometimes referred to as “soft obligations”, largely because they are ancillary to some other obligation and do not themselves attract a legal sanction for non-compliance.

Driedger’s view is not universally held (see, for example the article on Expressing Obligations and Prohibitions in the Canadian drafting manual, Legistics). The choice between “shall” and “must” has become a matter of differing drafting practices in different jurisdictions. The terms are increasingly seen as interchangeable. At the same time, take care not to use both in the same instrument, as this may suggest differences in meaning.

Activity 4

Is “must” now a permitted alternative or a required replacement for “shall” in your jurisdiction? Or is “shall” still the term in favour to impose an unqualified duty or prohibition?

If the duty is to refrain from acting in a prescribed way, under a threat of a penalty, most Legislative counsel use “shall not” (or “must not”). This conventionally is the strongest form of prohibition.

But could such a command equally well be given by using “may not”? Does this not deny a person the right to act?

Example 32

A person may not carry on a business of dealing in second-hand motor vehicles without a dealer’s licence.

On its face, this auxiliary has the same effect as an unqualified duty. But strictly, the provision is negativing or denying the holding of a power, permission or right, rather than commanding that the person refrain from doing the act. Accordingly “may not” is more useful to emphasise that some power, permission or right provided for by law is withdrawn.

Example 33

  1. (1) A trustee may apply to a Judge for directions with respect to the investment of trust funds.
  2. (2) A trustee of a trust established outside Utopia may not apply under subsection (1).
  • Alternative approaches

    There are cases when a term other than “shall” or “must” can be used to express a mandatory requirement. Verb phrases like “is required to” or “is to” also create obligations. These phrases can be used when the context of a provision suggests that “shall” or “must” is too strong because no penal sanction is involved to enforce the obligation.

Example 33A

The Minister is to establish the form of notice.

The inspector is required to give prior notice of any inspection under the Act.

A person who is exempted under section 5 is not required to notify the Registrar of any change in personal information.

  • Universal prohibitions

    If the sentence is to create a universal prohibition (one that affects everyone or everyone in a specific class), the conventional practice is to negative the person rather than the verb: “No person shall ......”. This is both more emphatic and, strictly, the correct converse of the rule that requires everyone to do something.

Example 34

Of the following, the first version makes the stronger impact:

No person shall drop litter in a public place.

A person shall not drop litter in a public place.

Can we use “no person must .....” instead? In fact, this does not work in quite the same way. Strictly, it is a statement that no one is under an obligation to act in the prescribed way. That is not the same as commanding persons not to act in that way.

Example 35

No person must walk on the grass in a public park.

This means that no one is under a duty to walk on the grass, although they may if they wish! This is precisely what is not required.

The conventional practice is:

  • introduce a universal prohibition by “No person shall”.
  • if you wish to use “must”, adopt the following : “A person must not .....”.
  • if you wish to emphasise that a particular person is not under an obligation (for example, but other persons are), use “No police officer is required to .....”

Powers and Permissions

In a sentence that gives the subject a power or permission to act or not to act, the predicate must confer the necessary authority. Although power and permission are distinct concepts, they are often dealt with by the same auxiliary “may”.

  • Powers

A power is an authority to do something that would otherwise be illegal or tortious or legally ineffectual. It states the type of action that the subject can legally choose to initiate or is permitted to take if deciding to act. Typically, in conferring a power four questions need to be answered:

  1. Is the person to have a discretion to decide whether or not to exercise the power, or must the power be exercised when specified circumstances occur?
  2. Are grounds to be specified that must be fulfilled before the power is exercised? If so, is the person to have a discretion to decide whether those grounds are fulfilled?
  3. Is the person to have discretion to decide the means by which the power is to be exercised or are these to be specified?
  4. Is the power to be coupled with a duty, for example as to how discretion is to be exercised or as to conditions to be attached when permission is granted? If so, what are the consequences if the duty is not complied with?

In conferring a power, legislative counsel generally use “may” as the auxiliary.

Example 36

The Minister may make regulations for carrying this Act into effect.

The Minister is authorised to make any necessary regulations.

A power expressed in this way is usually taken to give the holder discretion as to whether or not to exercise it. It is not usually necessary to add words to confirm the discretion. However, it is sometimes necessary to couple a power with a duty to exercise it in prescribed circumstances. This can lead to problems of interpretation if “may” rather than “shall” or “must” is used.

Example 37

The Minister may issue a licence on payment by the applicant of the prescribed fee.

Is the Minister under a duty to issue a licence when the payment is made (does the applicant have a right to a licence merely by paying the fee? If so, “shall” or “must” is the appropriate auxiliary. Or can the Minister refuse the licence even though payment is tendered (is the Minister to have a discretion)?

The simple use of “may” is not conclusive, since it can leave unclear whether the power is discretionary or whether its exercise is obligatory. The context in which the term is used may provide the answer. For example, if the holder has to make a judgment before exercising the power, it is clearly discretionary. At the same time, the courts will insist that the holder is under a duty to go through the process of making the judgment. A statement of the factors to be considered before exercising the power allows the courts to draw such a conclusion.

Example 38

The following provision gives councils a general authority to act in this way. But it is unclear whether councils are to have a power to issue permits in their unfettered discretion.

Every local government council may issue parking permits to owners of private motor vehicles who are resident in its area.

Can a council refuse permits if it thinks proper? Further provision is needed to set the framework within which the power is to be exercised.

If the power is to be exercised only when specified conditions exist, make clear whether those conditions are to be established objectively or whether the holder is to make a judgment in that respect. Similarly, if the way the power is to be put into effect is to be determined by the holder, make clear that this feature of the power is discretionary.

Example 39

If the Registrar is satisfied that a registered person is contravening any of the provisions of this Part, the Registrar may serve that person with an enforcement notice requiring him or her to take such steps as are specified in the notice for complying with this Part.

The Registrar may arrange for the publication of such information about the operation of this Act as appear to him or her expedient to give to the public. The information is to be published in the form and manner that the Registrar considers appropriate.

In drafting a power:

  • use “may” as the standard auxiliary when a person is authorised to act but need not do so, and especially where an element of discretion is involved;
  • if (but only if) there is any danger that a duty will be implied when that is not intended, add an appropriate modifier, for example “in the Minister’s discretion”; “if the Minister considers expedient” or “thinks fit”; “if the officer is satisfied that there are grounds for doing so”;
  • if a duty to act is intended, consider using “shall” or “must” in the predicate.

Practice what you have learned. It is time to complete exercise 8.

Use the “Navigation” menu on the left to click on “Activities” and then “Quizzes” to find the Exercises.

  • Permissions

    Rules are often needed to regulate previously uncontrolled activities by giving permission for them to be carried on in the future, for example if prescribed conditions or requirements are met or complied with. This can be dealt with in two ways:

    • by permitting the activity (using “may”) if the prescribed circumstances are fulfilled;
    • by prohibiting the activity (for example using “must not”) unless the prescribed circumstances are fulfilled.

    Legislative counsel generally prefer the second of these approaches (a “qualified prohibition”) even though it uses a negative form to authorise a positive activity. Although a positive form is more quickly understood, the negative states categorically that permission is wholly dependent upon fulfilling the condition. If a positive form is used, make clear that fulfilling the condition is a pre-requisite of having permission.

Example 40

A person may carry on a business of dealing in second-hand motor vehicles only if that person holds a dealer’s licence issued under this Act.

No person shall carry on a business of dealing in second-hand motor vehicles unless that person holds a dealer’s licence issued under this Act.

A person must not carry on a business of dealing in second-hand motor vehicles unless that person holds a dealer’s licence issued under this Act.

  • Denial of authority

    In a rule that precludes the subject from exercising a power or denies permission to act, the predicate must be drafted to withhold or withdraw the authority. Legislative counsel generally achieve this by using “may not”. However, if you are seeking to prohibit behaviour rather than prevent the exercise of a power, it is sensible to use “shall not / must not”.

Example 41

  1. 12. An inspector may enter any premises at any time to inspect electrical installations, but may not enter a residence on a Sunday.
  2. 20. A person contravening any provision of this Act commits an offence.

Is the inspector under a duty not to enter on Sundays, in which case a breach can be punished under section 20? Or is the purpose of the auxiliary to withhold the power of entry (breach of which might give rise to civil consequences only)?

If the former, it is clearer to write:

..... but an inspector must not enter a residence on a Sunday.


Legislation that, for example, establishes a new body typically must state the competencies of that body: its jurisdiction, responsibilities and functions (the general activities that enable it to carry out the purposes for which it was created.

  • “May” generally used to confer competencies

Example 42

The Commission may investigate complaints about judges subordinate to the High Court.

This sentence both designates the Commission as the body to carry out this activity and authorises it to do so. However, it gives the impression of a power, making the decision to investigate a matter of discretion, when its purpose is to state an activity that the body is obliged to carry out. The extent to which the body is to have discretion in performing the function is better dealt with as a distinct issue.

If the objective of a provision is to confer responsibility for a particular activity, more specific words can be used, especially if it involves a duty to act.

Example 43

The Commission has the function of investigating complaints about judges subordinate to the High Court.

A district court has jurisdiction to hear and determine actions founded on contract or tort if the debt, demand or damage does not exceed $5000.

  • “Shall” to confer competencies

    Legislative counsel in the past have also used “shall” to make an authority responsible for some activity. That auxiliary gives the impression of a legally enforceable duty to act when what is needed is to confer capacity to act with respect to the activity.

    An acceptable alternative that gives a less unqualified obligation is to use:

    • is [are] to,
    • is [are] not to,
    • is competent.

Example 44

Compare the two versions of each of the following sentences. The second removes any notion of compulsion in conferring competence to act.

  1. The members of the Board shall be appointed by the Minister.

    The members of the Board are to be appointed by the Minister.

  2. The District Court shall hear and adjudicate upon petitions for the dissolution of marriage.

The District Court is competent to hear and adjudicate upon petitions for the dissolution of marriage.


If the provision is to confer a right on the subject, legislative counsel conventionally achieve this by using “may”. Although this does not differentiate a right from a power, in most circumstances this is of little importance. A right to do things carries with it the power of action.

  • Right to a benefit

    But the power of action may not be intended if you are conferring a right to receive something or be benefited in some respect. To write “may receive”, for example, leaves quite uncertain whether there is some person who is under a duty to pay or merely whether the subject is capable of being made a beneficiary of another’s power, if it is exercised. A need for such an approach can arise:

    • automatically on the happening of some stated event;
    • following the exercise of another’s discretion.

    In cases of this kind, a right is better conferred by “is entitled”.

Example 45

A child under the age of 2 years is entitled to receive free school education if the Social Welfare Officer considers that the parents of the child are unable to pay the costs of school education.

If a farm animal trespasses on land, the occupier of the land may be paid compensation, as prescribed, by the owner of the animal.

Although the second example would be construed as creating a right in the occupier, it is better stated as:

...... is entitled to be paid compensation .........

Alternatively, the sentence could be drafted in the active voice to impose a duty to pay upon the owner of the animal, but that might not fit with a legislative context that is concentrating on the legal position of occupiers of land.

  • Disentitlement

    In a sentence that sets out to deny a particular class of person a right that is available to others, “is not entitled” is more effective than “may not”.

Example 46

If the owner or occupier of land kills or injures a dog in the course of protecting a farm animal threatened by that dog, the owner of the dog is not entitled to be paid compensation for the death or injury of the dog.


If the rule is to state that the subject is a proper person to perform a particular function, the predicate must declare the subject to be qualified. Conventionally, legislative counsel use “may”. In practice, this rarely causes confusion with powers or rights. But “is eligible” is a better auxiliary.

Example 47

The second version of the following is more explicit:

The following persons may be appointed directors of the corporation ...

The following persons are eligible to be appointed directors of the corporation ...

  • Disqualifications

In a sentence that excludes the subject from some receiving a benefit or performing a function, “is not eligible” or “is not qualified” can be used instead of “may not”.

Practice what you have learned. It is time to complete exercise 9.

Use the “Navigation” menu on the left to click on “Activities” and then “Quizzes” to find the Exercises.


If the provision is to make the subject vulnerable to legal actions by others, the predicate must declare this liability. Conventionally, legislative counsel use the passive form “may be” or “shall be liable to be”. But this use of “shall” suggests some form of obligation, which is not the case. Those cases are better dealt with by “is liable to be”.

Example 48

A person found trespassing on land belonging to the Railway Authority is liable to be [may be] prosecuted.


If the purpose of the rule is to prevent the subject from being liable, the predicate must create a privilege (it must negative any liability to the action of others). Some legislative counsel use “shall not be [liable]”. This implies a duty in unspecified persons not to act against the subject, when in fact the case is one of absence of power or competence. It is preferable to use “is not liable to be”.

Practice what you have learned. It is time to complete exercise 10.

Use the “Navigation” menu on the left to click on “Activities” and then “Quizzes” to find the Exercises.


If the provision is to give the subject directions to do or not do something, or as to how to do something, the predicate must give an instruction to the subject. Some legislative counsel use “shall” or “shall not” in these cases. But, again, this suggests that the subject is under some duty enforceable by a penalty. In many instances, that is not the aim of the sentence. Three types of direction can be distinguished, to which different auxiliaries are suited.

  • Direction as to composition or persons to perform a function

    The purpose of the sentence is to indicate how a body is to be composed or which person is the competent authority. As we have seen, you can use the present tense for this case, or “must”, or “is to”, or similar phrases.

Example 49

  1. 14. (1) The local government councils listed in the Schedule are established by this Act.
  2. (2) The councils are to be [must be] composed of the numbers of members as are respectively specified in that Schedule.
  • Direction as to how the subject is to perform a function

    The purpose of the sentence is to indicate how the subject, having decided to exercise a power, is to proceed. To use “shall”, as has often been the practice, gives the impression that the subject is under a sanctionable duty to act in the particular way. This may be caught by a general penalty clause that provides punishments for contraventions of the Act. This is rarely required. Yet, to use “may” suggests that the process is discretionary, rather than one to be performed in the manner directed.

Example 50

  1. 25. (1) A prospector who, in the course of prospecting for minerals in accordance with section 21, discovers minerals in commercial quantities may apply to the Minister for a mining licence.
  2. (2) The applicant must apply in the prescribed form within 2 months after discovering the minerals.

Subsection (2) intends that the set method of application should be followed, but “must” creates a stronger form of obligation than is needed.

Consider focusing the direction as to how to act on the resulting action (the “application”) into an adverbial phrase which modifies the verb stating the action itself.

  1. (2) The application must be made in the prescribed form within 2 months after discovering the minerals.

Practice what you have learned. It is time to complete exercise 11.

Use the “Navigation” menu on the left to click on “Activities” and then “Quizzes” to find the Exercises.

  • General direction as to procedure

    A sentence may prescribe the procedure to be followed in given circumstances. In many cases, the procedure is intended to be obligatory and some form of imperative language has to be used. Some drafters use “shall” or “must”. Some use “is to”, especially when setting out routine administrative procedures. However, from a legal standpoint, the important factor is the consequences that flow from failure to observe the obligation.

    These can take a variety of forms. Non-compliance can have penal consequences or invalidate the procedure or render void the outcome to which the procedure was leading. Alternatively, the procedure may be no more than the administratively convenient way of taking a matter forward without any consequences flowing from non-compliance.

    Such matters are not determined by the choice of auxiliary.

Example 51

All summonses, warrants, orders, convictions, recognisances, and all other processes, whether civil or criminal, must be issued or made, and be signed, by a magistrate or, if authorised by this Act, a justice of the peace.

Proceedings before a magistrate’s court are to be instituted either by the making of a complaint or, in the case of a person arrested without a warrant, by bringing the arrested person before the court.

Here the drafting practices in your jurisdiction should provide guidance. But do not expect the courts to treat these terms as conclusive. Courts generally decide these cases by taking account of such matters as the importance of the procedure in the legislative scheme, the interests that are affected, and who will be prejudiced by non-compliance, and to what extent.

If the consequences of non-compliance are important, but may be unclear from the context, do not rely on the choice of auxiliary to make this distinction clear. State expressly what the consequences are. For example, does failure to follow a particular procedure invalidate the action or merely permit the person to whom the procedure is directed to disregard the action if they so wish (for example refuse to consider an application not made in the correct form)? For a more extensive examination of this matter, see Duncan Berry, “Is it sufficient for legislative counsel merely to state the rules?”.

Example 52

No summons, warrant, order, conviction, recognisance, or other process, whether civil or criminal, is valid unless issued or made, and signed, by a magistrate or, if authorised by this Act, by a justice of the peace.

Unlike Example 51, this draft makes clear that non-compliance renders the processes void.

Activity 5

If your Interpretation Act contains a provision equivalent to the model Interpretation Act, section 44, note the reference.

Practice what you have learned. It is time to complete exercise 12.

Use the “Navigation” menu on the left to click on “Activities” and then “Quizzes” to find the Exercises.

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