Internal Aid of Interpretation (Marginal Notes, Headings, Definition) or Interpretation Clauses7 min read



The word interpretation has its roots in Latin term interpretari which means to expound, to understand, or to translate. Interpretation can be defined as the process of expounding which involves construing the ambiguous language of the statute.

According to Salmond interpretation or construction is “the process by which the courts seek to ascertain the meaning of the legislature through the medium of authoritative forms in which it is expressed”

According to Oxford Advanced Learner’s Dictionary ‘aid’ means “to help somebody to do something. Here; ‘aid’ will act as a noun which means a device that helps or assists.

While interpreting the provisions of a statute, the jurists may seek the help of both rules and aids of interpretation as was held in the case K.P. Verghese v. Income Tax Officer, Ernakulam, that interpretation of the statute is an exercise of ascertaining the meaning and everything should be admissible which is logically relevant. A rule is an established course of thing while aid is a device to help or to assist and for the construction or interpretation, the jurists take recourse of internal and external aids.

In simple words, internal aids can be called aids that derive the meaning of a provision or of a statute from the internal structure of the text and common dictionary meaning. Internal aids can also be called as ‘intrinsic aid’ so, they are “any material which is published within an Act, but is not a substantive provision of the Act.”

There are various types of internal aids which include, viz., title (short and long), marginal notes, headings, illustrations, preamble, punctuations, proviso, explanations, schedules, definition or interpretation clause, exceptions and saving clauses.

Now, external aids are those which aid which helps in deriving the meaning of the statute from external sources and are used when internal aids are not sufficient. In B. Prabhakar Rao v. State of Andra Pradesh, O. Chennappa Reddy J. stated that “Where internal aids are not forthcoming, we can always have recourse to external aids to discover the object of the legislation. External aids are not ruled out. This is not a well-settled principle of modern statutory construction”. Further in the case of the District Mining Officer and Ors. v. Tata Iron & Steel Co., the Supreme Court held that external aids are brought to widen the context and it is the cardinal principle of construction.

There are various types of external aids which include viz., dictionaries, foreign decisions, textbooks, historical background, legislative history, administrative conveyancing, and commercial practice.

Internal Aid (Marginal Notes, Headings, Definition or Interpretation Clauses)

Marginal Notes

Marginal notes are also known as headnotes or side notes. They express the effect of the section. According to Sullivan “the short notations appearing above or beside each section of an Act or Regulation.” Marginal Notes have this name because originally they appeared in the margins of the statute next to the relevant provisions. The purpose of marginal notes is to help readers in identifying pertinent provisions of the statute.

They are not considered as the part of legislation despite appearing in the act or regulation but Sullivan categorically disapproved this by stating that ’’All though technically marginal notes are not considered part of the legislation, in fact, they are physically present and may well constitute the most frequently read component of many Acts and regulations to ignore whatever light they shed on the meaning of legislation seems artificial and appropriate.’’

In the case of Wilkes v. Goodwin it was held that marginal notes are not the integral part of the Act and hence they cannot be referred.

But there are various case laws in which marginal notes have been used as interpretation tool as in the case of Imperial Oil Ltd. v. Canada; Inco Ltd. v. Canada it was held that ’’ although marginal notes are not entirely devoid of usefulness, their value is limited for a court that must address a serious problem of statutory interpretation.’’

The Supreme Court in Bengal Immunity Company v. the State of Bihar held that the marginal notes attached to Article 286 of the Constitution are part of the statute (Constitution of India). So therefore it could be relied on to furnish an interpretation of the Article.

Further in the case of Tara Prasad Singh and Ors. v. Union of India and Ors. it was held that marginal notes attached to a section of legislation cannot take away the effect of the provisions

In the Supreme Court case of S. P. Gupta v. Union of India It was held that if the pertinent provisions in the body of a statute are firmly pointing towards construction that would be in conflict with the marginal notes, the marginal note has to yield further the Supreme Court stated that in case of ambiguity in the meaning of the statute, the marginal notes may be looked into as an aid to construction.


Headings are like a preamble which helps as a key to the mind of the legislature but do not control the substantive section of the enactment. Headings can be used as the key to interpreting the objective portion of the section.

There are two types of headings:

1. One which is prefixed to a section; and

2. Another which is prefixed to a group or set of sections

In Shelly v. London Country Council, it was stated that a heading given to a group of sections can’t act as an aid to another group of sections. But headings can be used to interpret unclear provisions. But headings of the section have a very limited role to play in the interpretation of statutes.[18] But will be relied on while interpreting Section 5, 3(d), 2(l) (j) (a) of the Patents Act, 1970.

 In Union of India v. Abn Amro Bank it was said if there is no confusion in the language used in the provision then the heading strengthens the meaning                            

In the case of Krishnaiahv. State of Andhra Pradesh and Ors. it was held that the headings prefixed to the sections can’t control the plain words of the provisions. Only in the case of doubt on ambiguity headings may be consulted as an aid in interpretation.

So, headings can be used to clear doubt and ambiguity in the interpretation of the provision and to ascertain the legislative intent.  (N.C. Dhoundilal v. Union of India (2003)).

Definition or Interpretation Clauses

Sometimes legislature propounds its own legal definition and if that definition is included in the statute it will be binding on the courts. Sometimes the common words are used in the different statute hence their meaning needs to be interpreted separately.  Words used do not have clear meaning sometimes, so, they are assigned with the definition. Whenever the words ‘means or means and include’ are used, they make definition exhaustive.

In Mayor of Portsmouth v. Smith, Lord Watson observed that the introduction of interpretation clause is a novelty.

 But if the word ‘includes’ is used then the wide interpretation is possible. In M/s. Humdard(Wakf) Laboratories v. Deputy Labour Commissioner [22] the Supreme Court stated that when an interpretation clause uses the word ’includes’, it is prima facie extensive.  Further in Ramanlal Bhailal Patel v. the State of Gujarat, it was held that the usage of ‘includes’ indicates an intention to extend the meaning of the word in the statute.

In Jagir Singh v. State of Bihar the court held that the usage of the word ’includes’ provides a wider concept to the word ‘owner’.

If definition clause results in an absurd outcome then the application of definition or definition clause is not possible as one act can’t be used in another statute except in pari materia.

In Mahalaxmi Oils Mills v. State of Andhra Pradesh question regarding the interpretation of word tobacco was raised. The Supreme Court held that the definition is exhaustive and tobacco seeds cannot be included under the definition of tobacco.

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