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UK Public General Acts

Version 25/04/2013

1978 CHAPTER 30

Default Geographical Extent: E+W+S+N.I.

Introductory Text

Interpretation Act 1978

1978 CHAPTER 30

An Act to consolidate the Interpretation Act 1889 and certain other enactments relating to the construction and operation of Acts of Parliament and other instruments, with amendments to give effect to recommendations of the Law Commission and the Scottish Law Commission.

[20th July 1978]


Modifications etc. (not altering text)

C1 Act modified (E.W.S.) by Road Traffic Regulation Act 1984 (c. 27, SIF 107:1), s. 144, Sch. 10 para. 19

C2 Act: definition of "subordinate legislation" applied (E.W.) (1.12.1991) by Water Industry Act 1991 (c. 56, SIF 130), ss. 219(1), 223(2) (with ss. 82(3), 186(1), 222(1), Sch. 13 paras. 1, 2, Sch. 14 para. 6)

Act: definition of "subordinate legislation" applied (E.W.) (1.12.1991) by Water Resources Act 1991 (c. 57, SIF 130), ss. 221(1), 225(1)

C3 Act applied (1.4.1995) by S.R. 1995/71, arts. 1(1)(a), 2(2)

Act applied (with modifications) (27.9.1999) by S.I. 1999/2453, reg. 3

Act applied (1.1.2001) by S.I. 2000/2047, rule 2(2)

Act applied (1.7.2001) by S.I. 2000/2048, rules 1, 2(2); Instrument dated 21.6.2001 made by the Archbishops of Canterbury and York

Act applied (27.9.2001) by S.I. 2001/3057, Sch. para. 5(2)

Act applied (1.6.2004) by The Veterinary Surgeons and Veterinary Practitioners (Disciplinary Committee) (Procedure and Evidence) Rules Order of Council 2004 (S.I. 2004/1680), art. 2, {Sch. rule 2.3}

C4 Act applied in part (1.3.2007) by The Social Security Investigation Powers (Arrangements with Northern Ireland) Regulations 2007 (S.I. 2007/271), reg. 3(1), Sch. 1 para. 5

C5 Act applied (26.11.2008) by Pensions Act 2008 (c. 30), ss. 73(1), 149(2)(a)

Commencement Information

I1 Act wholly in force at 1.1.1979, see s. 26

General provisions as to enactment and operation

1 Words of enactment.

Every section of an Act takes effect as a substantive enactment without introductory words.

2 Amendment or repeal in same Session.

Any Act may be amended or repealed in the Session of Parliament in which it is passed.

3 Judicial notice.

Every Act is a public Act to be judicially noticed as such, unless the contrary is expressly provided by the Act.

4 Time of commencement.

An Act or provision of an Act comes into force—

(a) where provision is made for it to come into force on a particular day, at the beginning of that day;
(b) where no provision is made for its coming into force, at the beginning of the day on which the Act receives the Royal Assent.

Interpretation and construction

5 Definitions.

In any Act, unless the contrary intention appears, words and expressions listed in Schedule 1 to this Act are to be construed according to that Schedule.

6 Gender and number.

In any Act, unless the contrary intention appears,—

(a) words importing the masculine gender include the feminine;
(b) words importing the feminine gender include the masculine;
(c) words in the singular include the plural and words in the plural include the singular.

Modifications etc. (not altering text)

C6 S. 6(a) excluded (E.W.) by Sexual Offences Act 1985 (c. 44, SIF 39:5), ss. 4(3), 5(5)

C7 S. 6(b) excluded (E.W.) by Sexual Offences Act 1985 (c. 44, SIF 39:5), ss. 4(3), 5(5)

C8 S. 6(b) excluded (E.W.S.) by Employment Act 1989 (c. 38, SIF 43:1), ss. 5(4)(7), 29(6), Sch. 9 para. 4(1)

7 References to service by post.

Where an Act authorises or requires any document to be served by post (whether the expression “serve” or the expression “give” or “send” or any other expression is used) then, unless the contrary intention appears, the service is deemed to be effected by properly addressing, pre-paying and posting a letter containing the document and, unless the contrary is proved, to have been effected at the time at which the letter would be delivered in the ordinary course of post.


Modifications etc. (not altering text)

C9 S. 7 modified (E.W.) (1.7.1995) by 1994 c. 36, s. 17(2)(3) (with s. 20); S.I. 1995/1317, art. 2

C10 S. 7 excluded by Insurance Companies Act 1982 (c. 50, SIF 67), s. 77(4)

S. 7 excluded (E.W.) by Enduring Powers of Attorney Act 1985 (c. 29, SIF 1), s. 4(3), Sch. 1 Pt. IV para. 8(2)

S. 7 excluded by Public Order Act 1986 (c. 64, SIF 39:2), s. 11(5)

S. 7 excluded (20.6.2003) by The Enterprise Act 2002 (Merger Prenotification) Regulations 2003 (S.I. 2003/1369), regs. 5, 11, 12, 13(5)

S. 7 excluded (E.W.) (1.7.2005 for certain purposes and 1.8.2005 otherwise) by Serious Organised Crime Act 2005 (c. 15), ss. 133(6), 178; S.I. 2005/1521, arts. 3(1)(p), 4(1)

S. 7 excluded (E.W.) (1.10.2007) by The Mental Capacity Act 2005 (c. 9), ss. 66(3), 68(1), Sch. 4 para. 12 (with ss. 27-29, 62); S.I. 2007/1897, art. 2(1)(d)

8 References to distance.

In the measurement of any distance for the purposes of an Act, that distance shall, unless the contrary intention appears, be measured in a straight line on a horizontal plane.

9 References to time of day.

Subject to section 3 of the M1 Summer Time Act 1972 (construction of references to points of time during the period of summer time) , whenever an expression of time occurs in an Act, the time referred to shall, unless it is otherwise specifically stated, be held to be Greenwich mean time.


Marginal Citations

M1 1972 c. 6.

10 References to the Sovereign.

In any Act a reference to the Sovereign reigning at the time of the passing of the Act is to be construed, unless the contrary intention appears, as a reference to the Sovereign for the time being.

11 Construction of subordinate legislation.

Where an Act confers power to make subordinate legislation, expressions used in that legislation have, unless the contrary intention appears, the meaning which they bear in the Act.


Modifications etc. (not altering text)

C11 S. 11 applied (1.1.1995) by S.I. 1994/3144, reg. 1(6)

C12 S. 11 excluded (E.W.) (1.9.1997) by S.I. 1997/1972, reg. 2(3)

C13 S. 11 applied (30.10.2005) by The Medicines (Traditional Herbal Medicinal Products for Human Use) Regulations 2005 (S.I. 2005/2750), regs. 1, 2(3) (with transitional provisions in reg. 12, Sch. 6)

C14 S. 11 excluded (S.) (1.8.2007) by The Education (Fees and Awards) (Scotland) Regulations 2007 (S.S.I. 2007/152), reg. 2(2)

C15 S. 11 excluded (W.) (31.8.2007) by The Education (Fees and Awards) (Wales) Regulations 2007 (S.I. 2007/2310), reg. 2(2)

C16 S. 11 excluded (S.) (1.8.2012) by The Education (Fees) (Scotland) Regulations 2011 (S.S.I. 2011/389), regs. 1(1), 2(2)

Statutory powers and duties