On equating ‘mays’ with ‘musts’: When can a discretionary power be interpreted as a mandatory one?

• Author: Draga, L.
• DOI: https://doi.org/10.47348/SALJ/v138/i3a9
• Published date: 09 September 2021
• Date: 09 September 2021
• Pages: 649-681

649

ON EQUATING ‘MAYS’ WITH ‘MUSTS’:

WHEN CAN A DISCRETIONARY POWER BE

INTER PRETED AS A M ANDATORY ONE?

LISA DR AGA†

Lecturer, School of L aw, University of the Western Cap e

In this articl e I investigate when the other wise permissi ve term ‘may’ in an empow ering

provision can b e interpreted a s imposing a duty on the re cipient of that po wer to act.

In the rst part, I e xamine our cour ts’ pre-democrat ic approach to an swering thi s

question through an a nalysis of pre-dem ocratic judgment s. In particular, I scr utinise

certain fac tors that the cou rts have tradition ally relied on in this regard. T hereafte r,

I consider the pre sent-day rule s of statutory int erpretation a nd its applicat ion to

the may/must question. Next, I analyse th e Constitutional Co urt’s approach to

determining w hen the use of ‘may’ to confer a pow er through statute can be inter preted

as requiring th e power be exercised. I underta ke an analysis of a dissection of releva nt

Constitutional C ourt judgments. T hese judgments a re dissected for pur poses of

illustrating the cont inued relevance of the traditional fac tors that were employed before

democracy. Finally, I focus on th e may/must question in the ty pical public-law conte xt

of this interp retative exerci se. I examine potentia l grounds of revie w where the holder

of the power ha s failed or refused to exe cute a duty attac hed to permissi ve language.

I also consider se paration-of- powers conc erns that may l ikely arise.

Discretion – permis sive – mandatory – power

I INTRODUCTION

Law school teaches that the statutor y use of the word ‘may’ can be

interprete d, in a given context, as ‘must’ and t hat ‘must’ can be interprete d,

in tur n, as ‘may’. Also taught is the de fault position that , absent a compellin g

context to the contrary, a ‘must’ ordinarily imputes a ‘must’ and a ‘may’

ordinar ily imputes a ‘may’.1 However, for ‘as long as the English language

retain s its meaning “may” can never be equ ivalent to “must”’.2 It would be

nonsensical to advocate otherwise.3 The question that then presents itself

is when can a may be interpreted as a must? In other words, when can the

ostensibly per missive ter m ‘may’ be interpreted as mandatory?

Our courts are confronted with this question in situations where

obligations are created or powers bestowed through apparently dis cre-

tionar y language i n a legal provision and t he court must determ ine whether

† LLB (Western Cape) LLM ( Universit y of Missou ri, Columbia). ht t p s :// o r c id .

org/0000-0002-8456-3112. Thank s go to Sarah Fick, Wessel le Roux and Kessler

Peruma lsamy for their contribut ions to this article.

1 Cora Hoex ter Administrative L aw in South Afr ica (2007) 47; J R de Ville

Constitutional and Statutory Inter pretation (2000) 260.

2 Schwartz v Schwartz 1984 (4) SA 467 (A) at 474C–D, refer ring to Noble &

Barbour v Sout h African R ailways and Harbour s 1922 AD 527 at 540.

3 R v Dietrich 1946 EDL 57 at 61–2.

https://doi.org/10.47348/SALJ/v138/i3a9

(2021) 138 SALJ 649

© Juta and Company (Pty) Ltd

650 (2021) 138 THE SOU TH AFRICAN LAW JOUR NAL

https://doi.org/10.47348/SALJ/v138/i3a9

the holder of the power is mand ated to exercise that power.4 This article

is aimed,  rst, at explor ing the pre-constitut ional approach to answering

the above question through an ana lysis of relevant pre-democratic case

law. I distil and d iscuss cer tain factors that the courts have traditionally

relied upon to reach either a m andator y or a discret ionary meaning.

The present-day rules of statutory i nterpretation and its application to the

may/must question are thereaf ter exam ined.

Next, the article scrut inises the Constitut ional Cour t’s approach to

determi ning whether an ostensibly permissive empowering provision

can be read as m andator y. This is undertaken through an exposition of

the most relevant Constitutiona l Court cases. These cases are ana lysed

for purposes of determining to what extent the Const itutional Court has

referred to and applied the trad itional ( pre-const itutional) factors when

deciding this issue. Through this analysis this article seek s to determine

whether the court, although not explicitly, has nonetheless assim ilated

some of the traditional factors into its interpretat ive approach. This

article speculates to what extent, if any, courts may rely on the traditional

factors when r uling on future ca ses. Fina lly, this article focuses on the

may/must question in the typical public-law context of this interpretative

process. It considers potential g rounds of rev iew under the Promotion of

Admin istrative Justice Act (‘PAJA’)5 for a power-bearer’s failure or refusal

to execute a duty attached to perm issive language. A potential review

stemming from the breach of the principle of legality is also considered.

Final ly, separation-of-powers concerns are discussed.

II THE PRE-DEMOCRATIC STANCE ON ‘MAYS’ AN D

‘MUSTS’

Due to the dier ing dominant theor ies of interpretation at times in

our legal history, the inquiry as to when a may can be inter preted as a

must in the context of a n empowering prov ision is era depend ant. In the

pre-constitutional age, an answer to this question would have necessitated

4 Courts have al so engaged with the question whether a ‘must’ c an be

interpret ed as a ‘may’ where procedural re quirement s for the perfor mance

of an act have been st atutor ily set and the court is requ ired to dete rmine t he

consequences of a l ack of compliance. Here the court must label the prov ision

peremptor y (full compliance need ed) or direc tory (subst antia l compliance will

suce). See Chri sto Botha St atutory Inter pretation: An Introd uction for Student s

4 ed (2005) 109; G E Devenish Interpr etation of Statut es 2 ed (1996) 223; L M du

Plessis The Interpretation of Statutes (1986) 143; F J van Heerden & A C Cr osby

Interpretation of Statutes (1996) 75. Schola rs have tended to xate on th is question,

and have neglec ted the question regarding when a ‘may’ can be interpre ted as a

‘must’ in the contex t of an empoweri ng provision : see Botha op cit at 109–13;

Devenish op cit at 223–35; Du Pless is op cit at 143–7; Van Heerden & Crosby

op cit at 75–8.

5 Act 3 of 2000.

© Juta and Company (Pty) Ltd

ON EQUATING ‘MAYS’ WIT H ‘MUSTS’ 651

https://doi.org/10.47348/SALJ/v138/i3a9

a discussion of the Golden Rule of interpretation. A lso essential to

that discussion would be the cour ts’ repeated and extensive reliance

on Julius v Bishop of Oxford (‘Julius’).6 The part below focuses on the

pre-democratic jurisprudentia l method of determining whether an

ostensibly per missive empowering provision carried an attendant

obligation on the power-holder to act.

(a) The Golden R ule

The Golden Rule is aimed at establ ishing legislat ive intent through

examining the language of the text.7 Where words are clear and

unambig uous, the clear mea ning must prevail.8 Under the rule, courts

looked beyond the gram matica l meaning if that meaning would lead to

absurd results or if the provision permitted ambiguity.9 A court would

not, without cogent reasons, depar t from the ordinary meaning attached

to ‘may’.10 A deviation could occur to give eect to the man ifest intent

of the legislature.11 The onus was on wh ichever of the litigants sought a

mandator y interpretation to prove th at this interpret ation was warranted .12

The courts m ade clear that no univer sal rule could be la id out as to when

a ‘may’ could be read as a ‘must’.13 Where courts explored words beyond

their gra mmatical mea ning, they made use of va rious techniques to cla ssify

‘may’ as discretionary or obligator y. This included the use of common-

law presumptions of statutor y interpretation. These presumptions served

as principles that aided courts when construing legislat ion.14 Courts

were even prepared to consider extraneous factors to determine if a

mandator y meani ng applied.15 Whether a section contained guidelines as

6 (1880) 5 AC 214.

7 De Ville op cit note 1 at 94.

8 Ibid.

9 W le Roux ‘Directory provisions, section 39(2) of the Cons titution a nd the

ontology of st atutory l aw: Afric an Christian D emocratic Par ty v Electoral Co mmission

2006 (3) SA 305 (CC)’ (2006) 21 SA Public L aw 382.

10 African Commerc ial and Distri butive Workers’ Union v Scho eman, NO & anothe r

1951 (4) SA 266 (T) at 274.

11 Amalgamated Pack aging Industri es Ltd v Hutt & anoth er 1975 (4) SA 943 (A)

at 950D.

12 Hartley NO v T he Master 1921 AD 403 at 407–8; Blo emfontein Town Council v

Bloemfontei n Licence Certi cate Board & another 1927 OPD 19 at 21–2; R v Zock 192 8

AD 384 at 389; Lyn ch v Union Government (Min ister of Justice) 1929 AD 281 at 284;

Desai v Wessels and Torlage & anoth er 1964 (1) SA 783 (D) at 787.

13 Custodia n of Enemy Prope rty v Brakpan Mi nes, Ltd 1922 TPD 179 at 188;

Rex v Dietri ch supra note 3 at 62.

14 Annie Singh ‘A re-eva luation of the com mon-law presu mptions of inter-

pretation in the light of t he Constitution’ (2012) 75 THRHR at 79 and De Vil le

op cit note 1 at 164.

15 Chief Pass O cer, Johannesbur g v Mashamba 1917 AD 397 at 404; Groen ewald

v Minister of Fina nce 1927 TPD 679 at 690; Minister of Defen ce v Bourke 1950 (1) SA

393 (A) at 397; Hall v Military Pen sions Appeal Tribunal 1963 (3) SA 407 ( T).

© Juta and Company (Pty) Ltd