The US record industry won a key victory in court this week after a Minnesota woman was found guilty of copyright infringement and ordered to pay $220,000 to six music labels.

The courtroom battle between single mother Jammie Thomas, 30, and the recording industry is an important test case because it is the first time that a consumer has elected to forgo settlement and argue the case before a jury.

Thomas was accused of the illegal sharing of more than 1,700 songs on peer-to-peer network Kazaa. The charge was later cut to 24 songs.

The woman claimed in her defence that she has never used Kazaa and does not have a Kazaa account.

The case could set a dangerous precedent, in that the owner of an internet account could be held responsible for any file sharing taking place from that connection, such as children using a family computer.

Around 26,000 people are thought to have been sued by the Recording Industry Association of America (RIAA) since 2003, almost all of whom have settled out of court for a few thousand dollars.

However, many industry watchers expect that the case is far from over and that an appeal is likely.

The case also highlighted some curious thinking by the record companies. For example, an executive for Sony BMG stated that the act of copying a music track from a CD to a media player is an act of theft.

"When an individual makes a copy of a song for himself, I suppose we can say he stole a song," said Jennifer Pariser, head of litigation and anti-piracy at Sony BMG.

Making a "copy" of a purchased song, she said, is just "a nice way of saying 'steals just one copy'".

Pariser also acknowledged that the money spent on lawsuits such as this is not being recovered from the pirates, and that the RIAA is making a loss.

When questioned on the stand Pariser admitted that the recording industry had no idea how much money it had lost to file sharing.