Search Legislation

Computer Misuse Act 1990

 Help about what version

What Version

 Help about advanced features

Advanced Features

 Help about opening options

Opening Options

Status:

Point in time view as at 01/01/2006. This version of this cross heading contains provisions that are not valid for this point in time. Help about Status

Close

Status

Not valid for this point in time generally means that a provision was not in force for the point in time you have selected to view it on.

Changes to legislation:

There are currently no known outstanding effects for the Computer Misuse Act 1990, Cross Heading: Miscellaneous and general. Help about Changes to Legislation

Close

Changes to Legislation

Revised legislation carried on this site may not be fully up to date. At the current time any known changes or effects made by subsequent legislation have been applied to the text of the legislation you are viewing by the editorial team. Please see ‘Frequently Asked Questions’ for details regarding the timescales for which new effects are identified and recorded on this site.

Miscellaneous and generalU.K.

10 Saving for certain law enforcement powers.U.K.

  • Section 1(1) above has effect without prejudice to the operation—

    (a)

    in England and Wales of any enactment relating to powers of inspection, search or seizure; and

    (b)

    in Scotland of any enactment or rule of law relating to powers of examination, search or seizure

    [F1and nothing designed to indicate a withholding of consent to access to any program or data from persons as enforcement officers shall have effect to make access unauthorised for the purposes of the said section 1(1).

  • In this section “enforcement officer” means a constable or other person charged with the duty of investigating offences; and withholding consent from a person “as” an enforcement officer of any description includes the operation, by the person entitled to control access, of rules whereby enforcement officers of that description are, as such, disqualified from membership of a class of persons who are authorised to have access.]

Textual Amendments

F1Words in s. 10 inserted (3.2.1995) by 1994 c. 33, s. 162(1); S.I. 1995/127, art. 2(1), Sch. 1

11 Proceedings for offences under section 1.E+W+N.I.

(1)F2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(2)Subject to subsection (3) below, proceedings for an offence under section 1 above may be brought within a period of six months from the date on which evidence sufficient in the opinion of the prosecutor to warrant the proceedings came to his knowledge.

(3)No such proceedings shall be brought by virtue of this section more than three years after the commission of the offence.

(4)For the purposes of this section, a certificate signed by or on behalf of the prosecutor and stating the date on which evidence sufficient in his opinion to warrant the proceedings came to his knowledge shall be conclusive evidence of that fact.

(5)A certificate stating that matter and purporting to be so signed shall be deemed to be so signed unless the contrary is proved.

F3(6). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(7)This section does not extend to Scotland.

12 Conviction of an offence under section 1 in proceedings for an offence under section 2 or 3.E+W+N.I.

(1)If on the trial on indictment of a person charged with—

(a)an offence under section 2 above; or

(b)an offence under section 3 above or any attempt to commit such an offence;

the jury find him not guilty of the offence charged, they may find him guilty of an offence under section 1 above if on the facts shown he could have been found guilty of that offence in proceedings for that offence brought before the expiry of any time limit under section 11 above applicable to such proceedings.

(2)The Crown Court shall have the same powers and duties in relation to a person who is by virtue of this section convicted before it of an offence under section 1 above as a magistrates’ court would have on convicting him of the offence.

(3)This section is without prejudice to section 6(3) of the M1Criminal Law Act 1967 (conviction of alternative indictable offence on trial on indictment).

(4)This section does not extend to Scotland.

Marginal Citations

13 Proceedings in Scotland.S

(1)A sheriff shall have jurisdiction in respect of an offence under section 1 or 2 above if—

(a)the accused was in the sheriffdom at the time when he did the act which caused the computer to perform the function; or

(b)any computer containing any program or data to which the accused secured or intended to secure unauthorised access by doing that act was in the sheriffdom at that time.

(2)A sheriff shall have jurisdiction in respect of an offence under section 3 above if—

(a)the accused was in the sheriffdom at the time when he did the act which caused the unauthorised modification; or

(b)the unauthorised modification took place in the sheriffdom.

(3)Subject to subsection (4) below, summary proceedings for an offence under section 1, 2 or 3 above may be commenced within a period of six months from the date on which evidence sufficient in the opinion of the procurator fiscal to warrant proceedings came to his knowledge.

(4)No such proceedings shall be commenced by virtue of this section more than three years after the commission of the offence.

(5)For the purposes of this section, a certificate signed by or on behalf of the procurator fiscal and stating the date on which evidence sufficient in his opinion to warrant the proceedings came to his knowledge shall be conclusive evidence of that fact.

(6)A certificate stating that matter and purporting to be so signed shall be deemed to be so signed unless the contrary is proved.

(7)Subsection (3) of [F4section 136 of the Criminal Procedure (Scotland) Act 1995] (date of commencement of proceedings) shall apply for the purposes of this section as it applies for the purposes of that section.

(8)In proceedings in which a person is charged with an offence under section 2 or 3 above and is found not guilty or is acquitted of that charge, he may be found guilty of an offence under section 1 above if on the facts shown he could have been found guilty of that offence in proceedings for that offence commenced before the expiry of any time limit under this section applicable to such proceedings.

(9)Subsection (8) above shall apply whether or not an offence under section 1 above has been libelled in the complaint or indictment.

(10)A person found guilty of an offence under section 1 above by virtue of subsection (8) above shall be liable, in respect of that offence, only to the penalties set out in section 1.

(11)This section extends to Scotland only.

Textual Amendments

F4Words in s. 13(7) substituted (1.4.1996) by 1995 c. 40, ss. 5, 7(2), Sch. 4 para. 77

14 Search warrants for offences under section 1.E+W

(1)Where a circuit judge is satisfied by information on oath given by a constable that there are reasonable grounds for believing—

(a)that an offence under section 1 above has been or is about to be committed in any premises; and

(b)that evidence that such an offence has been or is about to be committed is in those premises;

he may issue a warrant authorising a constable to enter and search the premises, using such reasonable force as is necessary.

(2)The power conferred by subsection (1) above does not extend to authorising a search for material of the kinds mentioned in section 9(2) of the M2Police and Criminal Evidence Act 1984 (privileged, excluded and special procedure material).

(3)A warrant under this section—

(a)may authorise persons to accompany any constable executing the warrant; and

(b)remains in force for [F5three months] from the date of its issue.

(4)In executing a warrant issued under this section a constable may seize an article if he reasonably believes that it is evidence that an offence under section 1 above has been or is about to be committed.

(5)In this section “premises” includes land, buildings, movable structures, vehicles, vessels, aircraft and hovercraft.

(6)This section does not extend to Scotland.

Extent Information

E1This version of this provision extends to England and Wales only; a separate version has been created for Northern Ireland only.

Textual Amendments

Modifications etc. (not altering text)

Marginal Citations

14 Search warrants for offences under section 1.N.I.

(1)Where a circuit judge is satisfied by information on oath given by a constable that there are reasonable grounds for believing—

(a)that an offence under section 1 above has been or is about to be committed in any premises; and

(b)that evidence that such an offence has been or is about to be committed is in those premises;

he may issue a warrant authorising a constable to enter and search the premises, using such reasonable force as is necessary.

(2)The power conferred by subsection (1) above does not extend to authorising a search for material of the kinds mentioned in section 9(2) of the M2Police and Criminal Evidence Act 1984 (privileged, excluded and special procedure material).

(3)A warrant under this section—

(a)may authorise persons to accompany any constable executing the warrant; and

(b)remains in force for twenty-eight days from the date of its issue.

(4)In executing a warrant issued under this section a constable may seize an article if he reasonably believes that it is evidence that an offence under section 1 above has been or is about to be committed.

(5)In this section “premises” includes land, buildings, movable structures, vehicles, vessels, aircraft and hovercraft.

(6)This section does not extend to Scotland.

Extent Information

E2This version of this provision extends to Northern Ireland only; a separate version has been created for England and Wales only

Modifications etc. (not altering text)

Marginal Citations

15 Extradition where Schedule 1 to the Extradition Act 1989 applies.U.K.

F6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Textual Amendments

F6S. 15 repealed (1.1.2004) by Extradition Act 2003 (c. 41), ss. 219, 220, 221, Sch. 3 para. 7, Sch. 4; S.I. 2003/3103, art. 2 (subject to savings in order arts 3-5 as amended by S.I. 2003/3312 and S.I. 2003/3258)

16 Application to Northern Ireland.U.K.

(1)The following provisions of this section have effect for applying this Act in relation to Northern Ireland with the modifications there mentioned.

(2)In section 2(2)(b)—

(a)the reference to England and Wales shall be read as a reference to Northern Ireland; and

(b)the reference to section 33 of the M3Magistrates’ Courts Act 1980 shall be read as a reference to Article 46(4) of the M4Magistrates’ Courts (Northern Ireland) Order 1981.

(3)The reference in section 3(6) to the M5Criminal Damage Act 1971 shall be read as a reference to the M6Criminal Damage (Northern Ireland) Order 1977.

(4)[F7Subsection (7) below shall apply in substitution for subsection (3) of section 7]; and any reference in subsection (4) of that section to England and Wales shall be read as a reference to Northern Ireland.

F8(5). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

F8(6). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(7)The following paragraphs shall be inserted after Article 3(1) of that Order—

(1A)Subject to section 8 of the Computer Misuse Act 1990 (relevance of external law), if this paragraph applies to an act, what the person doing it had in view shall be treated as an offence to which this Article applies.

(1B)Paragraph (1A) above applies to an act if—

(a)it is done in Northern Ireland; and

(b)it would fall within paragraph (1) as more than merely preparatory to the commission of an offence under section 3 of the Computer Misuse Act 1990 but for the fact that the offence, if completed, would not be an offence triable in Northern Ireland..

(8)In section 8—

(a )F8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(b)the reference in subsection (3) to section 1(1A) of the M7Criminal Attempts Act 1981 shall be read as a reference to Article 3(1A) of that Order.

(9)The references in sections 9(1) and 10 to England and Wales shall be read as references to Northern Ireland.

(10)In section 11, [F9before subsection (2) there shall be inserted]

(1)A magistrates’ court for a county division in Northern Ireland may hear and determine a complaint charging an offence under section 1 above or conduct a preliminary investigation or preliminary inquiry into an offence under that section if—

(a)the accused was in that division at the time when he did the act which caused the computer to perform the function; or

(b)any computer containing any program or data to which the accused secured or intended to secure unauthorised access by doing that act was in that division at that time.;

F10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

(11)The reference in section 12(3) to section 6(3) of the M8Criminal Law Act 1967 shall be read as a reference to section 6(2) of the M9Criminal Law Act (Northern Ireland) 1967.

(12)In section 14—

(a)the reference in subsection (1) to a circuit judge shall be read as a reference to a county court judge; and

(b)the reference in subsection (2) to section 9(2) of the M10Police and Criminal Evidence Act 1984 shall be read as a reference to Article 11(2) of the M11Police and Criminal Evidence (Northern Ireland) Order 1989.

Valid from 01/10/2008

[F1116ANorthern Ireland: search warrants for offences under section 1N.I.

(1)Where a county court judge is satisfied by information on oath given by a constable that there are reasonable grounds for believing—

(a)that an offence under section 1 above has been or is about to be committed in any premises, and

(b)that evidence that such an offence has been or is about to be committed is in those premises,

he may issue a warrant authorising a constable to enter and search the premises, using such reasonable force as is necessary.

(2)The power conferred by subsection (1) above does not extend to authorising a search for material of the kinds mentioned in Article 11(2) of the Police and Criminal Evidence (Northern Ireland) Order 1989 (privileged, excluded and special procedure material).

(3)A warrant under this section—

(a)may authorise persons to accompany any constable executing the warrant; and

(b)remains in force for twenty-eight days from the date of its issue.

(4)In exercising a warrant issued under this section a constable may seize an article if he reasonably believes that it is evidence that an offence under section 1 above has been or is about to be committed.

(5)In this section “premises” includes land, buildings, movable structures, vehicles, vessels, aircraft and hovercraft.

(6)This section extends only to Northern Ireland.]

17 Interpretation.U.K.

(1)The following provisions of this section apply for the interpretation of this Act.

(2)A person secures access to any program or data held in a computer if by causing a computer to perform any function he—

(a)alters or erases the program or data;

(b)copies or moves it to any storage medium other than that in which it is held or to a different location in the storage medium in which it is held;

(c)uses it; or

(d)has it output from the computer in which it is held (whether by having it displayed or in any other manner);

and references to access to a program or data (and to an intent to secure such access) shall be read accordingly.

(3)For the purposes of subsection (2)(c) above a person uses a program if the function he causes the computer to perform—

(a)causes the program to be executed; or

(b)is itself a function of the program.

(4)For the purposes of subsection (2)(d) above—

(a)a program is output if the instructions of which it consists are output; and

(b)the form in which any such instructions or any other data is output (and in particular whether or not it represents a form in which, in the case of instructions, they are capable of being executed or, in the case of data, it is capable of being processed by a computer) is immaterial.

(5)Access of any kind by any person to any program or data held in a computer is unauthorised if—

(a)he is not himself entitled to control access of the kind in question to the program or data; and

(b)he does not have consent to access by him of the kind in question to the program or data from any person who is so entitled [F12but this subsection is subject to section 10.]

(6)References to any program or data held in a computer include references to any program or data held in any removable storage medium which is for the time being in the computer; and a computer is to be regarded as containing any program or data held in any such medium.

(7)A modification of the contents of any computer takes place if, by the operation of any function of the computer concerned or any other computer—

(a)any program or data held in the computer concerned is altered or erased; or

(b)any program or data is added to its contents;

and any act which contributes towards causing such a modification shall be regarded as causing it.

(8)Such a modification is unauthorised if—

(a)the person whose act causes it is not himself entitled to determine whether the modification should be made; and

(b)he does not have consent to the modification from any person who is so entitled.

(9)References to the home country concerned shall be read in accordance with section 4(6) above.

(10)References to a program include references to part of a program.

Textual Amendments

F12Words in s. 17(5)(b) inserted (3.2.1995) by 1994 c. 33, s. 162(2); S.I. 1995/127, art. 2(1), Sch. 1

18 Citation, commencement etc.U.K.

(1)This Act may be cited as the Computer Misuse Act 1990.

(2)This Act shall come into force at the end of the period of two months beginning with the day on which it is passed.

(3)An offence is not committed under this Act unless every act or other event proof of which is required for conviction of the offence takes place after this Act comes into force.

Back to top

Options/Help

Print Options

Close

Legislation is available in different versions:

Latest Available (revised):The latest available updated version of the legislation incorporating changes made by subsequent legislation and applied by our editorial team. Changes we have not yet applied to the text, can be found in the ‘Changes to Legislation’ area.

Original (As Enacted or Made): The original version of the legislation as it stood when it was enacted or made. No changes have been applied to the text.

Point in Time: This becomes available after navigating to view revised legislation as it stood at a certain point in time via Advanced Features > Show Timeline of Changes or via a point in time advanced search.

Close

See additional information alongside the content

Geographical Extent: Indicates the geographical area that this provision applies to. For further information see ‘Frequently Asked Questions’.

Show Timeline of Changes: See how this legislation has or could change over time. Turning this feature on will show extra navigation options to go to these specific points in time. Return to the latest available version by using the controls above in the What Version box.

Close

Opening Options

Different options to open legislation in order to view more content on screen at once

Close

More Resources

Access essential accompanying documents and information for this legislation item from this tab. Dependent on the legislation item being viewed this may include:

  • the original print PDF of the as enacted version that was used for the print copy
  • lists of changes made by and/or affecting this legislation item
  • confers power and blanket amendment details
  • all formats of all associated documents
  • correction slips
  • links to related legislation and further information resources
Close

Timeline of Changes

This timeline shows the different points in time where a change occurred. The dates will coincide with the earliest date on which the change (e.g an insertion, a repeal or a substitution) that was applied came into force. The first date in the timeline will usually be the earliest date when the provision came into force. In some cases the first date is 01/02/1991 (or for Northern Ireland legislation 01/01/2006). This date is our basedate. No versions before this date are available. For further information see the Editorial Practice Guide and Glossary under Help.

Close

More Resources

Use this menu to access essential accompanying documents and information for this legislation item. Dependent on the legislation item being viewed this may include:

  • the original print PDF of the as enacted version that was used for the print copy
  • correction slips

Click 'View More' or select 'More Resources' tab for additional information including:

  • lists of changes made by and/or affecting this legislation item
  • confers power and blanket amendment details
  • all formats of all associated documents
  • links to related legislation and further information resources