A criminal investigation has been launched against two prominent Italian Internet providers because they allowed their customers to access the BitTorrent site BTjunkie. The ISPs are suspected of aiding and abetting online copyright infringement, after they ignored a court order to block subscriber access to the popular BitTorrent search engine.

Earlier this year an Italian court ordered a nationwide blackout of the country’s most-used torrent site BTjunkie. Italian ISPs were ordered to block both the IP addresses of the site and its domain name as the BitTorrent site is an alleged hotbed for online piracy.

The owner of BTjunkie was not informed about the action. “I’m disappointed with the Italian judicial system,” he tol TorrentFreak at the time. “We will do our best to fight for Italian people’s right to communicate.”

This promise was kept and a few days later BTjunkie launched a proxy site which allowed Italian users to circumvent the block. However, for many Italians the proxy wasn’t needed as the ISPs Fastweb and NGI reportedly failed to block the popular torrent site.

This failure to comply with the court order has now prompted the Cagliari court to launch a criminal investigation into both ISPs who are suspected of aiding and abetting online copyright infringement. This is the first case in Italy where Internet providers are being held liable for the copyright-infringing actions of their subscribers.

The case against the two ISPs was prompted by an investigation by the Guardia di Finanza (GdF), the Italian police force with responsibility for dealing with cybercrime. They regularly monitor the traffic levels of �?pirate’ sites and found that not all Italian ISPs were adhering to the court order.

As expected, the legal action was welcomed by the Italian music industry group FIMI, who previously called for a total blackout of all piracy-related websites.

“We believe the action brought by the judiciary of Cagliari sends a very important signal that lawlessness can not be tolerated or encouraged in any way. Especially not from companies that offer telecommunication services, who have a key role in stopping copyright violations as required by law,” FIMI’s president Enzo Mazza said commenting on the news.

According to a response from Fastweb, the whole case stems from a technical failure. The Internet provider today stated that it was never their intention to allow subscriber access to BTjunkie, and actually resolved the error as soon as the news broke.

BTjunkie’s blockade is not the first Italian attempt at blacking out a popular torrent site. The court order is similar to an earlier Italian block of The Pirate Bay that was first handed down in 2008. After an appeal process of nearly two years, The Pirate Bay was eventually blocked both completely and permanently last year.

Whether Fastweb and NGI’s failure to block BTjunkie was an accident or a deliberate attempt to bypass the court order will become clear in the coming weeks.