Computer Misuse Act 1990

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 [F1 or to enable such access to be secured]) 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 [F2 but 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) F3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

[F4 (8) An act done in relation to a computer is unauthorised if the person doing the act (or causing it to be done)—

(a) is not himself a person who has responsibility for the computer and is entitled to determine whether the act may be done; and

(b) does not have consent to the act from any such person.

In this subsection “ act ” includes a series of acts. ]

(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

F1 Words in s. 17(2) inserted (S.) (1.10.2007) by Police and Justice Act 2006 (c. 48), ss. 52, 53, Sch. 14 para. 29(2) (with s. 38(1)); S.S.I. 2007/434, art. 2 (the inserting provision being repealed for E.W.N.I. (1.10.2008) by 2007 c. 27, ss. 61(5), 92, 94, Sch. 14 (with Sch. 13 para. 5); S.I. 2008/2504, art. 2(a)(i)(viii))

F2 Words 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

F3 S. 17(7) repealed (1.10.2007 for S. and 1.10.2008 otherwise) by Police and Justice Act 2006 (c. 48), ss. 52, 53, Sch. 14 para. 29(3), Sch. 15 Pt. 4 (with s. 38(4)); S.S.I. 2007/434, art. 2; S.I. 2008/2503, art. 2

F4 S. 17(8) substituted (1.10.2007 for S. and 1.10.2008 otherwise) by Police and Justice Act 2006 (c. 48), ss. 52, 53, Sch. 14 para. 29(4) (with s. 38(4)); S.S.I. 2007/434, art. 2; S.I. 2008/2503, art. 2