In a development with implications for the European Commission (EC) investigation into net neutrality, European Court of Justice (ECJ) Advocate General (AG) Pedro Cruz Villalon concluded in an advisory opinion that a Belgian court order that forces Internet service providers (ISPs) to filter or block web content in the interest of preventing unauthorized downloads of copyrighted material violates the fundamental rights of Internet users. The case at hand pits Scarlet Extended, a Belgian ISP, against music royalty service Saban, which sued against unauthorized swaps of its copyrighted content over peer-to-peer (P2P) web services. After determining that such infringements had occurred, the Belgian court ordered Scarlet to block or filter all P2P web transmissions for illegal material within six months. Saban, however, sought to have that order overturned before the Court of Appeal in Brussels. That tribunal, in turn, asked the ECJ whether the European Union’s Charter of Fundamental Rights permits a national court to order ISPs to install content filtering or blocking systems on their networks. Determining that the filtering and blocking activities mandated by the Belgian court restrict rights to privacy and freedom of expression guaranteed by the Charter, Villalon noted in an opinion handed down last Thursday that restrictions on Internet transmissions are permissible only if they are ordered under laws that are clear, predictable and accessible. As such, Villalon concluded that any requirement forcing ISPs to install filtering or blocking systems at their own expense—even for the purpose of preventing illegal activity—constitutes a special obligation that is not tied to any specific law. While acknowledging that EU courts are permitted under law to order actions that are aimed at stopping specific incidents of online infringement, Villalon maintained that the law cannot be extended to encompass across-the-board filtering or similar preventive actions that affect all Internet users. Although Villalon’s opinion is not considered to be legally binding, observers say that the ECJ usually follows the AG’s recommendations.