A private member's Bill passed last week gives the police rights to search business premises and seize equipment if firms are using unregistered copies of commercial software.
Lawyers believe that software suppliers will use the Copyright Design and Patents Act 2002 to initiate high-profile raids against businesses suspected of flouting the law, as a deterrent to others.
"Here is an inexpensive quick way to bring action. The main purpose of any actions will be a deterrent effect. It may seem unfair and wrong but it's the publicity aspect that is very important," said Robin Fry, partner in law firm Beachcroft Wansbroughs.
The new Act makes it an offence punishable by a fine of up to £5,000 per item to use unlicensed software. But the publicity impact of a police raid, and disruption resulting from seizure of equipment, could be far more damaging.
In the past software suppliers have used civil law to pursue businesses suspected of using unlicensed software, but this can be expensive and time-consuming.
Rachel Burnett, a partner at law firm Bristows, said companies should audit their software to ensure that they stay within the law.
But keeping track of all software in an organisation can be difficult, say IT directors. "The big problem is the 'golden disc', where you legally have a master copy of a piece of software and can make copies of it. Every month you are supposed to reconcile how many copies you have. But it is easy to forget to note it down," said Roger Ellis, former IT director at Blue Circle.
David Rippon, chairman of the Elite Group of IT directors, said that Microsoft's near monopoly might have encouraged some businesses to skimp on licensing. But, he said, "Two wrongs don't make a right."