Computer Misuse Act 1996, unauthorised access and modification offences
A citation is an address, not a summary. The first part names the law; what follows narrows it to the exact section, article or paragraph.
In force.
A computer misuse rule binding public and private bodies.
As of 7 September 2026.
What it requires
- Do not cause a computer to perform any function to secure access to a program or data without being entitled to control that access or having the consent of someone who is, and knowing the access is unauthorised.
- Do not modify computer material, or cause a computer to cease to function, without authorisation.
If you get it wrong
Criminal exposureYes
Criminal exposure note
Unauthorised access (section 3) is liable on summary conviction to imprisonment for six months or a fine of $6,000, or both. Unauthorised access with intent to commit a further offence (section 4), unauthorised modification (section 5), and causing a computer to cease to function (section 6A) are each liable on summary conviction to imprisonment for six months or a fine of $6,000, or both, and on conviction on indictment to imprisonment for five years or a fine of $20,000, or both.
Penalty structure
Sections 4, 5 and 6A cap a fine at $20,000 (five years' imprisonment) on conviction on indictment; the base unauthorised-access offence under section 3 carries a lower $6,000 summary-only cap (six months' imprisonment).
- Rule
- Fixed only
- As of
- 7 September 2026
- Currency
- BMD
- Fixed cap
- 20,000
What it reaches
Obligation class
Access restriction
What this law does
Drafted with AI from the cited sources under the direction of UnGovr staff. UnGovr holds editorial responsibility for this page.
Section 3 makes it an offence for a person, knowing the access is unauthorised, to cause a computer to perform any function with intent to secure access to a program or data held in any computer, whether or not the intent is directed at a particular program, data or computer. Access is unauthorised only if the person is not entitled to control access of that kind and lacks the consent of someone who is, so authorisation rather than a technical measure is what the Act tests.
Section 4 aggravates the offence where the unauthorised access is committed with intent to commit or facilitate a further indictable offence. Section 5 separately criminalises unauthorised modification of computer material, and section 6A unauthorised conduct causing a computer to cease to function permanently or temporarily. The Act's text does not carry a separate commencement clause beyond the date of assent.
When LexLint raises it
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