The perceived loophole was a small one. The original legislation did not squarely address "denial of service" attacks, in which a company's systems are maliciously bombarded with data to the point of collapse. The furthest the 1990 Act went was to describe an offence of causing "unathorised modification of the contents of any computer" with criminal intent, such as hacking into your bank's computer and changing the balance of your account. But did that actually apply to denial of service attacks?

In November 2005, a district court judge suggested that it did not. Teenager David Lennon was cleared of criminal charges after he sent five million e-mails to his former employer, temporarily crashing the company's server, because the judge felt his actions were not covered by the Act. Mr Lennon's lawyer successfully argued that as the purpose of the company's server was to receive e-mails, the company had consented to the receipt of Mr Lennon's e-mails and their consequent modifications of data. As long as sending e-mails was an authorised act, the reasoning went, the fact that he had sent so many of them was irrelevant.

But by the time the High Court had issued that ruling, amendments to the legislation had already been tacked on to the Police and Justice Bill. It received Royal Assent last week, thus widening the Computer Misuse Act. It is now an offence to perform an unauthorised act in relation to a computer with the "requisite intent" and "requisite knowledge".

Will it make a difference? At best, the changes are a timely upgrade that remove any lingering doubts about the law. It is not a radical change. I do not see it resulting in more convictions. On the other hand, we still have only one piece of legislation explicitly and solely focusing on computer crime and for that simplicity we should be grateful. Contrast with the US, where fresh legislative proposals seem to emerge with each new warning about computer security.

Struan Robertson is a lawyer at Pinsent Masons specialising in technology and the editor of Out-Law.com. His column on technology law appears every Wednesday