The language of law and policy is fundamentally one of instruction, dictating duties, granting powers, and setting boundaries. In this high-stakes environment, clarity is not merely a virtue; it is a foundational requirement for enforceability and justice. For decades, one word—shall—has plagued this system, standing as the single greatest source of ambiguity in legal texts. However, the 21st century has ushered in a clear, consistent, and global mandate for precision, making the transition from shall to must the new standard for authoritative drafting.

The Ambiguity of the “Chameleon” Verb

The trouble with shall is its chameleon nature. It is simultaneously used to express a mandatory duty, a future tense, a permission, and occasionally, a direction. Bryan A. Garner, the leading advocate for plain legal language, warns that shall is one of the most misused words in the profession, arguing that “it’s better to use must for requirements and may for discretion” (Garner, 2021). This inherent polysemy forces judges and readers to parse the drafter’s intent through context, transforming a simple act of reading into an expensive and often needless act of interpretation.

The Global Trend: From “Shall” to “Must”

Across the U.K., Australia, Canada, and the U.S., a clear and irreversible trend is visible: legislative drafting bodies are systematically abandoning shall in favor of simpler, unambiguous modal verbs. This shift is part of a broader commitment to plain language principles, which ensures statutes and regulations are accessible and immediately comprehensible to citizens, regulators, and the courts.

Modal Verb	Function in Legal/Policy Drafting	Authority’s Recommendation
MUST	Imposes a strict, mandatory duty or requirement.	Recommended for all obligations.
MAY	Grants discretionary power or permission.	Recommended for all permissions.
SHOULD	States a non-mandatory best practice or strong recommendation.	Recommended for policy guidance.
SHALL	Traditional expression for a mandatory duty.	Avoided for new drafting.

Authoritative Guidance Across Jurisdictions

The movement away from shall is not a grassroots phenomenon but a top-down directive from the world’s most influential legislative drafting offices:

1. United Kingdom

The UK Office of the Parliamentary Counsel (OPC), responsible for drafting government Bills, has adopted a definitive policy: “Office policy is to avoid the use of the legislative shall. There may, of course, be exceptions” (Office of the Parliamentary Counsel (UK), 2024). Their guidance is direct: use must for obligations and may for permissions.

2. Australia

Australia’s approach is similarly unambiguous. The Office of the Parliamentary Counsel (Australia) states in its Drafting Manual that must “should be used where a duty is imposed” and may “should be used where a power or permission is discretionary” (Office of the Parliamentary Counsel (Australia), 2019). Drafting Direction No. 2.2 explicitly reinforces this preference for precision over tradition (Office of the Parliamentary Counsel (Australia), 2023).

3. Canada and the United States

The trend is cemented across North America, where various state and federal drafting guides in the U.S.—heavily influenced by Garner (2021)—and Canada have overwhelmingly adopted must to express binding requirements. This jurisdictional consistency has established must as the default marker for legal compulsion.

Practical Application in Compliance and Policy

For corporate drafters, especially those working on compliance policies or legal drafting in Bangladesh—where traditional drafting practices often lag behind global plain language standards—adopting this framework provides immediate risk mitigation.

• Risk Mitigation: Documents that mix shall and must create an unnecessary hierarchy of obligation, opening the door for legal challenges. A consistent use of must eliminates this vulnerability.
• Enforceability: In sectors like FinTech and Governance, a rule that states, “The Chief Risk Officer should conduct a periodic review,” is merely advisory. Changing it to “The Chief Risk Officer must conduct a periodic review” transforms it into an enforceable control, critical for internal audits and regulatory readiness.

The lesson from global authorities is simple yet profound: precision is the most sophisticated form of drafting. By aligning internal documents with the clear conventions established by the U.K., Australian, and U.S. drafting offices, organizations can ensure that their policies are not just grammatically correct, but legally sound.

References

Garner, B. A. (2021) Legal Writing in Plain English: A Text with Exercises, 3rd edn. Chicago: University of Chicago Press.

Office of the Parliamentary Counsel (Australia) (2019) OPC Drafting Manual, Edition 3.2. [online] Available at: https://www.opc.gov.au/publications/opc-drafting-manual (Accessed: 24 October 2025).

Office of the Parliamentary Counsel (Australia) (2023) Use of various expressions in draft legislation – Drafting Direction No. 2.2. [online] Available at: https://www.opc.gov.au/publications/use-various-expressions-draft-legislation (Accessed: 24 October 2025).

Office of the Parliamentary Counsel (UK) (2024) Drafting Guidance – 19 March 2024. [online] Available at: https://www.gov.uk/government/publications/drafting-bills-for-parliament/2024-03-19-drafting-guidance (Accessed: 24 October 2025).