Advocate General Paolo Mengozzi of the European Court of Justice upheld the rights of trade unions in two opinions Wednesday. In Laval v. Partneri (C-341/05) [opinion; press release, PDF in French], Mengozzi advised the court to allow trade unions to force companies from foreign EU member states to pay their workers the same that domestic workers would otherwise receive. Latvian construction company Laval was hired to build a school in Sweden, but Sweden's construction trade union Byggnads sought to force Laval to pay its workers more. In the second case, International Transport Workers' Federation v. Viking Line ABP (C-438/05), Mengozzi said trade unions should be able to act to dissuade a company from moving to another EU member state for the purposes of lowering wages.

Advocate General opinions are not binding, although generally the final opinions of the court, which will not be released for several months, follow them. By advocating more power for trade unions, Mengozzi seems to be granting greater weight to a country's internal autonomy, over the rules of the EU single market.