A judge has ordered British Telecom to begin blocking its subscribers from accessing Newzbin2, a members-only usenet search engine that is heavily used for copyright infringement. The mandated blocking is modeled on the Cleanfeed filtering system currently used to block alleged child pornography.

The original Newzbin was a UK company that billed itself as "Google for Usenet." It made hundreds of thousands of pounds helping its users find content—much of it infringing movies and television shows—on newsgroups. It disbanded last year after it was defeated in court by major copyright holders. But within months, Newzbin's source code began circulating on the Internet, and anonymous parties with servers in Sweden relaunched the service at the same domain.

So six major Hollywood studios went to court to compel BT, the UK's largest ISP, to block its subscribers from accessing the new service, dubbed "Newzbin2." BT opposed the request, and on Thursday the judge sided with the studios. He ordered BT to undertake an aggressive blocking program. While BT has discretion to decide on the exact methods employed, the judge recommended that BT use the Cleanfeed system that BT is currently using to block access to sites on a list of alleged child pornography provided by the Internet Watch Foundation.

The ruling represents a first step toward broader use of Internet filtering as a tool for blocking copyright infringement in the UK. "The Studios have made it clear that this is a test case," the judge wrote. "If they are successful in obtaining an order against BT, then they intend to seek similar orders against all the other significant ISPs in the UK."

The judge's order relied on the European Union's 2001 Information Society Directive, as implemented by the UK Parliament in 2003. That law states that a court can "grant an injunction against a service provider, where that service provider has actual knowledge of another person using their service to infringe copyright."

BT argued that when its subscribers access Newzbin2, BT is acting as a mere conduit for their network activity. Therefore, BT said, these users were not "using [BT's] service to infringe copyright." But the judge rejected this interpretation, holding that "users are using BT’s service to infringe copyright," and that he therefore has the authority to grant the injunction.