America’s Supreme Court has ruled that makers of peer-to-peer file-swapping technology can be held responsible for the copyright infringement that their products allow. This may stop much of the free downloading of music and film over the internet, but it will not cure the entertainment business’s ills. Nor will it do much for innovation

Last weekend over 110,000 music fans paid £125 ($228) each to attend the Glastonbury festival in Britain’s West Country and hear their favourite bands perform. In years gone by, many thousands more attended than paid, as less scrupulous festival-goers jumped the fence to watch the bands for free. The organisers stamped out the practice by building a bigger and better barrier. On Monday June 27th, a ruling by America’s Supreme Court provided the entertainment industry with the means to build a bigger and better fence against the internet pirates who refuse to pay for music and film.

The court’s unanimous ruling said that Grokster and StreamCast Networks, two makers of file-sharing software, are liable for the breaches of copyright that their technology allows, thereby reversing the decisions of two lower courts. The case, originally brought by MGM, a big Hollywood film studio, was joined by 27 of the world’s leading film and music companies. The ruling means that the file-sharing firms can be sued by entertainment companies for the theft of copyright-protected material using their software.