The courts should consider replacing juries in complex computer crime trials with panels of specialist judges trained in IT, security experts said last week.
Their comments follow concerns that suspected computer criminals are increasingly turning to what has become known as the "Trojan defence" in an attempt to escape prosecution.
The Trojan defence was used successfully by teenager Aaron Caffrey, who was acquitted last month of charges of launching a denial of service attack against critical computer systems in the port of Houston in Texas.
Caffrey produced evidence from a systems administrator that showed hackers could have planted a Trojan programme on his computer, launched the denial of service attack and deleted all traces of their activities, leaving Caffrey to take the blame.
Speaking at the Compsec information security conference last week, Richard Starnes, director of incident response at Cable & Wireless, said he was worried that genuine computer criminals would be able to use similar defences to escape prosecution.
He called for the law to be changed so that anyone bringing a Trojan defence would have to show in court that there was evidence that their machines had been compromised.
Detective sergeant Steve Santorelli, network investigator at Scotland Yard’s Computer Crime Unit, said the police had recently lost three cases because of the Trojan defence. Two of the cases involved alleged paedophiles.
"I think replacing the jury with three specialist judges is something that should be considered, but there is no silver bullet."
Peter Sommer, senior research fellow at the London School of Economics, who has acted as an expert witness in a number of internet paedophile cases, said that, in his experience, the Trojan defence was rarely successful.