Scarlet was recently ordered by a Belgian court to block its users from engaging in illegal file-sharing. It has now lodged an appeal against that ruling.
"This measure is nothing else than playing Big Brother on the Internet,'' said Scarlet managing director Gert Post in a statement. "If we don't challenge it today, we leave the door open to permanent, and invisible and illegal, checks of personal data."
Belgian Authors' rights group SABAM had taken a case against Scarlet asking the court to order it to screen traffic for material that would breach members' copyrights. A Belgian court surprised observers earlier this year when it ordered Scarlet to use screening technology to block such traffic.
Scarlet has now said that it believes that complying with the court order would force it to break the law. It said that Belgian phone tap laws prohibit it from eavesdropping on subscriber data transfers. It also said that Belgian privacy laws prevented it from the proactive monitoring of people's communications.
Scarlet also said that e-commerce laws stipulated that such activity is only appropriate in certain specific circumstances, and not as a general approach that can be taken with all customers.
The court had ordered that Scarlet use Audible Magic software to scan its traffic on peer to peer (P2P) networks to search for the unauthorised transfer of copyrighted material.
The ruling took many observers by surprise because it had been assumed that ISPs were protected by laws based on the EU's E-Commerce Directive rather than potentially conflicting laws based on the Copyright Directive.
The head of the legal work group at the Belgian ISP Association, Geert Somers, told OUT-LAW when the adjudication was announced that he believed that the E-Commerce Directive-based laws should take precedence.
"The E-Commerce directive needs to be seen as prevailing over the Copyright Directive," he told OUT-LAW Radio. "As a matter of fact the implementing legislation in Belgium at the moment is not entirely clear and I strongly believe the judge did not examine this relationship sufficiently,"
A SABAM spokesman said at the time that it had asked all of Belgium's ISPs to monitor traffic in the light of the ruling.
Scarlet said this week that the E-commerce Directive should protect it. "The E-Commerce Directive and the law are very clear: the ISP can in no case be held responsible for the information they transmit," said a Scarlet statement.
"In this situation, one can compare the ISP with a motorway," said Post. "As ISP, we are held responsible for the infringements for our customers on our network. In this case, will the owner of the motorway be also held responsible for the infringements made on the motorways?"