Computer Misuse Act 1990

[F1 3 Unauthorised acts with intent to impair, or with recklessness as to impairing, operation of computer, etc. U.K.

(1) A person is guilty of an offence if—

(a) he does any unauthorised act in relation to a computer;

(b) at the time when he does the act he knows that it is unauthorised; and

(c) either subsection (2) or subsection (3) below applies.

(2) This subsection applies if the person intends by doing the act—

(a) to impair the operation of any computer;

(b) to prevent or hinder access to any program or data held in any computer; [F2 or]

(c) to impair the operation of any such program or the reliability of any such data; [F3 or

(d) to enable any of the things mentioned in paragraphs (a) to (c) above to be done.]]

(3) This subsection applies if the person is reckless as to whether the act will do any of the things mentioned in paragraphs (a) [F4 to (d)][F4 to (c)] of subsection (2) above.

(4) The intention referred to in subsection (2) above, or the recklessness referred to in subsection (3) above, need not relate to—

(a) any particular computer;

(b) any particular program or data; or

(c) a program or data of any particular kind.

(5) In this section—

(a) a reference to doing an act includes a reference to causing an act to be done;

(b) “act” includes a series of acts;

(c) a reference to impairing, preventing or hindering something includes a reference to doing so temporarily.

(6) A person guilty of an offence under this section shall be liable—

(a) on summary conviction in England and Wales, to imprisonment for a term not exceeding [F5 the general limit in a magistrates’ court] or to a fine not exceeding the statutory maximum or to both;

(b) on summary conviction in Scotland, to imprisonment for a term not exceeding [F6 12] months or to a fine not exceeding the statutory maximum or to both;

(c) on conviction on indictment, to imprisonment for a term not exceeding ten years or to a fine or to both.

Textual Amendments

F1 S. 3 substituted (1.10.2007 for S. and 1.10.2008 otherwise) by Police and Justice Act 2006 (c. 48), ss. 36, 53 (with s. 38(3)(4)(6)); S.S.I. 2007/434, art. 2; S.I. 2008/2503, art. 2 (the substituting provision being amended for E.W.N.I. (1.10.2008) by 2007 c. 27, ss. 61(3), 94 (with Sch. 13 para. 5); S.I. 2008/2504, art. 2(a))

F2 Word at the end of s. 3(2)(b) inserted (E.W.N.I.) (1.10.2008) by virtue of Serious Crime Act 2007 (c. 27), ss. 61(3)(a)(i), 94 (with Sch. 13 para. 5); S.I. 2008/2504, art. 2(a)

F3 S. 3(2)(d) and preceding word repealed (E.W.N.I.) (1.10.2008) by virtue of Serious Crime Act 2007 (c. 27), ss. 61(3)(a)(ii), 92, 94, Sch. 14 (with Sch. 13 para. 5); S.I. 2008/2504, art. 2(a)(i)(viii)

F4 S. 3(3): Words "to (c)" substituted for words "to (d)" (E.W.N.I.) (1.10.2008) by virtue of Serious Crime Act 2007 (c. 27), ss. 61(3)(b), 94 (with Sch. 13 para. 5); S.I. 2008/2504, art. 2(a)

F5 Words in s. 3(6)(a) substituted (7.2.2023 at 12.00 p.m.) by The Judicial Review and Courts Act 2022 (Magistrates’ Court Sentencing Powers) Regulations 2023 (S.I. 2023/149), regs. 1(2), 2(1), Sch. Pt. 1 table

F6 Word in s. 3(6)(b) substituted (3.5.2015) by Serious Crime Act 2015 (c. 9), s. 88(1), Sch. 4 para. 7(c); S.I. 2015/820, reg. 2(r)(iii)