Just one third of illegal downloaders would stop their file sharing activities if they received a warning letter from their ISP, says Wiggin.
But research by the legal firm also revealed that 80 percent of those pirating music and video from the web would stop if they thought the letter would be followed by a loss of internet connection.
According to the Strategic Advisory Board for Intellectual Property (SABIP) around 7m Brits are using a file-sharing network once a week to illegally download music files, and dealing with the problem is one of the issues that will be covered in the government's Digital Britain report, which is expected to be released on June 17.
However, there is much conflict over how best to deal with the problem. The music industry has been campaigning for some time for a 'three strikes' rule that would see ISPs issue warning letters to those caught illegally downloading, followed by disconnection from the web for repeat offenders.
However, Culture Secretary Andy Burnham told a music industry conference this week that "technical solutions" would be used to prevent music and film being pirated, rather than disconnection from the web.
Although Burnham didn't detail exactly what solutions would be used, he said they would "limit or restrict" file-sharing activity. It is though that this will involve slowing the broadband access speed of repeat offenders.
"If you try speed humps or disconnections for peer-to-peer, people will simply disguise their traffic or share the content another way," Dunstone told the Guardian.
"It is more about education and allowing people to get content easily and cheaply that will make a difference," said Dunstone.
"A letter would not be enough," said Alexander Ross from Wiggin. "It does take an ultimate sanction."
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