Defence lawyers for Napster late Friday urged a federal appeals court to dismiss a lower court ruling that could effectively shut down the popular online music-swapping service. Separately, Napster's chief executive told reporters the company has tried to settle a recording industry lawsuit but said the Recording Industry Association of America (RIAA) has rebuffed all offers. In its brief submitted to the US 9th Circuit Court of Appeals, Napster lawyers argued that the injunction ordered in July by US district judge Marilyn Hall Patel was based on a faulty interpretation of copyright law. The appeals court temporarily stayed that injunction, hours before it was to have taken effect. The brief filed Friday urged the appeals court to make the stay permanent. Napster software allows users to download music files from one another's computers. In its copyright infringement lawsuit, the RIAA argued that Napster was responsible for the illegal trafficking of trademarked music titles over the Internet. The brief returned to the argument repeatedly made by Napster executives: that the decentralised nature of the service's peer-to-peer technology prevents the company from knowing how people use it. "Napster cannot distinguish between whether its users are engaged in fair or unfair uses," the company's lawyers argued. What's more, they said, Napster "is unable to distinguish files that are authorised for sharing from those that may be unauthorised." When that argument was made in front of Patel, she was having none of it, at one point declaring Napster had created a "monster" and had to live with the consequences. In a conference call with reporters late Friday, Jonathan Schiller, a partner in the law firm of Boies & Schiller, said "Napster is not liable. If our users are themselves not infringing, then we are not liable for contributory infringement." During the conference call, Schiller took aim at Patel, whom he said had misunderstood copyright infringement case law and had committed "evidentiary errors" in her ruling. The brief also argued that Patel erred in putting the burden of proof on Napster and by denying the company a full evidentiary hearing so that lawyers could dispute issues of fact in the case. "This was legal error," the defence brief declared, offering several examples of case law to support that contention. The RIAA will have until mid-September to file its response to Napster's filing, after which a court date will be set. In the conference call, Napster chief executive Hank Barry also disclosed that he had put forward "many proposals" for a settlement with the RIAA. All of them have been rejected, he said. Barry declined to be specific about the offers, although he said they provided for payments to artists whose works were traded on Napster. "We have been trying to propose structures that would compensate artists, and have been doing that from day one," Barry said. Take me to the MP3 Special What do you think? Tell the Mailroom. And read what others have said.