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What is the computer misuse act?

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In the UK, there are various laws in place which are designed to regulate the safe and proper use of computer systems. Many of these laws fall under the umbrella of the Computer Misuse Act 1990.

The Computer Misuse Act is wide in scope and is not necessarily restricted to prosecuting anyone who is found guilty of accessing a computer without permission. It’s therefore important to understand that the Act involves, the types of offences it relates to, and the potential sentences you could face if you are under investigation for said offences.

In this post, we discuss those issues in detail, as well as what you should do it you find yourself accused of a Computer Misuse Act offence.  

What is the Computer Misuse Act?

Established in 1990, the Computer Misuse Act provides clarification on the law surrounding lawful access to computer systems. Its primary function is to criminalise the unauthorised access of data, as well as the modification of information without the consent of the owner.

This means that causing a computer to perform a function with the intent of accessing specific programs or data would be an offence where:

  • Access to the program or data is unauthorised
  • The person is knowingly causing the computer to cause that function

There have been various amendments to the original act, including changes in 2015 which made life imprisonment possible where human welfare or national security is out at risk.

Definitions of computer

The CMA does not provide a definition of a computer because rapid changes in technology would mean any definition would soon become out of date.

Definition is therefore left to the Courts, who are expected to adopt the contemporary meaning of the word. In DPP v McKeownDPP v Jones ([1997] 2 Cr. App. R. 155, HL, at page 163), Lord Hoffman defined a computer as "a device for storing, processing and retrieving information."

Unauthorised use or access of mobile phones, tablets, laptops or any device that meets the above definition can be a computer.

We have been consulted for by ex-partners who have accessed devices belonging to a former partner to interfere with data that has been held.

What are computer misuse offences?

There are several offences which fall under the Computer Misuse Act 1990. As per the Crown Prosecution Service (CPS), the following offences apply:

  • Section 1: Unauthorised access to computer material
  • Section 2: Unauthorised access with intent to commit or facilitate commission of further offences
  • Section 3: Unauthorised Acts with intent to impair, or with recklessness as to impairing the operation of a computer
  • Section 3ZA: Unauthorised acts causing, or creating risk of, serious damage
  • Section 3A: Making, supplying or obtaining articles for use in offence under Section 1, 3, or 3ZA

The CPS also makes note of the fact that consideration may be given as to whether the most appropriate offence is being prosecuted. For example, many Computer Misuse Act offences are committed as a precursor to another offence such as fraud or blackmail.

As such, certain offences may be prosecuted under alternative Acts, including the Fraud Act 2006, the Investigatory Powers Act 2016 or the Data Protection Act 2018.

What evidence is used in Computer Misuse Act cases?

When investigating a suspected Computer Misuse Act offence, the police are highly likely to seize and interrogate any electronic devices that were allegedly used in the commission of the offence. In some cases, the police may also seek to access any information that was held in the cloud, alongside the actual contents of the devices.

Electronic records will also be heavily relied on by prosecutors. This may show when a system or computer was allegedly accessed, by whom and when. The prosecution may also look to link this unauthorised access to specific harm caused to the victim, or and additional offences which have allegedly been committed.

What are the sentencing guidelines for the Computer Misuse Act?

The potential Computer Misuse Act punishments that could be handed out vary significantly depending on the circumstances. Cases can be brought before either the Magistrates Court or Crown Court, with the different levels of Computer Misuse Act punishments being:

  • Unauthorised access to computer material – Maximum sentence of 2 years imprisonment
  • Unauthorised access with intent to commit or facilitate commission of further offences – Maximum sentence of 5 years imprisonment
  • Unauthorised Acts with intent to impair, or with recklessness as to impairing the operation of a computer – Maximum sentence of 10 years imprisonment
  • Unauthorised acts causing, or creating risk of, serious damage – Maximum sentence of 14 years imprisonment
    • OR life imprisonment where the offence caused or created significant damage to human welfare or national security
  • Making, supplying or obtaining articles for use in offence under Section 1, 3, or 3ZA – Maximum sentence of 2 years imprisonment

What defences are available for Computer Misuse Act offences?

The defences that may be available for a Computer Misuse Act offence will depend on the facts of the case. That said, there are some general defences that may apply, including:

  • You simply did not perform the act you were accused of committing
  • You performed the act, but were not aware an offence was being committed
    • This could be because you were not aware the relevant material was unauthorised and had legitimate reason to believe this
  • Your actions amounted to a mistake rather than malicious intent
  • Due to mental illness, you lacked the ability to reason that the act committed was against the law
  • You were forced to commit the act
  • You were not aware of your actions when committing the offence (excluding being under the influence of drugs or alcohol).

What should you do if you are accused of a Computer Misuse Act offence?

If you have been arrested for an offence in relation to the Misuse of Computers Act, it is vital that you arrange expert legal advice and representation as soon as possible. As discussed above, Computer Misuse Act punishments can be extremely serious, with life imprisonment being a possible consequence in some cases. Having the right support on side can help to ensure that your rights are upheld.

When accused of a Computer Misuse Act offence, it is essential that you understand what your case relates to and what actions may undermine your legal defence moving forward.

Contrary to what many people assume, speaking to a solicitor will not signify guilt in any way, nor will it negatively affect your legal position. No matter your circumstances, or the type of allegations you are facing, speaking to a solicitor at an early stage could make all the difference when it comes to avoiding charges or having charges reduced where conviction is unavoidable.

At JD Spicer Zeb, our expert team of specialist criminal defence solicitors have substantial experience in support individuals accused of various Computer Misuse Act offences. This means that we are well positioned to advise you on the defence strategies that are likely to be available for your case.

Pre-Charge Bail for Computer Misuse Act offences

If, after an interview for a Computer Misuse Act offence, you are released on pre-charge bail, this does not mean your case has concluded. The police will be continuing their investigation to gather more evidence before they make a final charging decision, and you will likely be subject to bail conditions.

To find out more in relation to pre charge bail please use the links provided below:

Contact our criminal law solicitors today

For urgent specialist advice, immediate representation or to speak to us confidentially about a Computer Misuse Act offence or any other criminal matter, please do not hesitate to contact our dedicated team of criminal defence lawyers in London, Birmingham and Manchester by telephone:

Or email: solicitors@jdspicer.co.uk

Alternatively, you can fill out our quick online enquiry form and we will get back to you as soon as possible.

24/7 legal representation for Computer Misuse Act offences

For immediate representation and advice, you can contact our emergency number 07836 577556 and we will provide you with the urgent assistance you need.

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