The rigorous demands for precision in statutes, regulations, and policy instruments mean that the choice between modal verbs is rarely trivial, as it directly determines the enforceability, scope, and interpretation of the document’s provisions. 

However, the legacy use of formal or archaic variants, particularly shall, has historically introduced significant ambiguity, leading to extensive judicial clarification and frustrating the goal of plain language legislation.

This article addresses this critical challenge by examining and synthesizing authoritative guidance—including legislative drafting manuals, key judicial interpretations, and leading linguistic recommendations—to establish a clear, consistent, and unambiguous framework for the deployment of modal verbs in contemporary legal and policy documents.

Why Modal Verbs Matter

In legal drafting, modal verbs do the heavy lifting.
They decide whether something must be done, may be done, or should be done. For example:

“Employees shall comply with the Code of Conduct.” → A mandatory legal duty.
“The Committee may recommend disciplinary action.” → A discretionary power.
“Managers should encourage ethical behaviour.” → A moral or advisory expectation.

A single misplaced modal verb can change the legal meaning of an entire clause.

What the Experts Say

UK Office of the Parliamentary Counsel (OPC)

The UK’s chief legislative drafting body has taken a firm stance:

“Office policy is to avoid the use of the legislative shall. There may, of course, be exceptions.” (UK OPC, Drafting Guidance, 2024)

Instead, the OPC directs drafters to use must for obligations and may for permissions. This ensures that readers—judges, regulators, and the public—instantly know whether a rule is compulsory or optional.

Bryan A. Garner: The Plain-Language Advocate

Bryan Garner, the renowned legal linguist and author of Legal Writing in Plain English (2021), warns that shall is one of the most misused words in legal writing:

“Shall is a chameleon that means different things at different times. It’s better to use must for requirements and may for discretion.”

Garner’s influence has spread beyond the U.S. to shape corporate governance drafting across the Commonwealth. His advice underpins the plain-language movement now embraced by many regulators and compliance professionals.

Australia’s Office of Parliamentary Counsel (OPC)

Australia’s drafters echo the same principle. The OPC Drafting Manual (2023) advises:

“May should be used where a power or permission is discretionary. Must should be used where a duty is imposed.”

This shift away from shall toward must reflects the global movement toward precision and readability in both legislative and corporate drafting.

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

Across the U.K., Australia, Canada, and the U.S., a clear trend is visible:

Must = Legal obligation

May = Discretion or permission

Should = Recommendation or moral expectation

Shall = Traditional, but increasingly avoided for new documents

Even in Bangladesh—where the legal drafting tradition still relies heavily on shall—modern corporate policies and governance documents are beginning to reflect this change. Internal charters, compliance frameworks, and AI governance policies benefit from the clarity that must brings.

Practical Implications for Corporate Drafting

In Contracts

Use shall or must for binding duties:
“The vendor must deliver reports within ten business days.”

Use may for options or discretion:
“The Company may renew this agreement annually.”

In Policies

Use must for compliance requirements:
“All employees must complete annual anti-bribery training.”

Use should for best practices:
“Managers should encourage open reporting of ethical concerns.”

In Governance Documents

Use may when the Board or a committee has power to act but no obligation.

Avoid mixing shall and must in the same document—choose one convention and apply it consistently.

Why It Matters for Governance and Fintech

In a regulated sector like fintech, precision is not optional—it’s compliance armor. Ambiguous verbs can weaken enforcement, cause interpretational disputes, or dilute accountability in oversight mechanisms.

For example, an AI Governance Policy that states,

“The Data Protection Officer should review algorithmic fairness annually,”
is a recommendation, not a legal requirement.

Replacing should with must turns it into an enforceable control:

“The Data Protection Officer must review algorithmic fairness annually.”

This one word can determine whether a policy holds up during an audit or regulatory inquiry.

Final thought

The evolution of modal verbs marks a broader transformation in legal drafting—from traditional formality to functional clarity. Whether drafting a Board Charter, a compliance policy, or an AI governance framework, the lesson from global authorities is simple:

Write what you mean, mean what you write—and choose your verbs wisely.

By aligning with plain-language standards from the UK, US, and Australian drafting offices, organizations can make their internal governance documents clearer, enforceable, and regulator-ready.

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