Presenting his conclusions on the Laval case on 23 May, Advocate-General Paolo Mengozzi argued that "where a member state has no system for declaring collective agreements to be of universal application", the Posting of Workers Directive "must be interpreted as not preventing trade unions from attempting, by means of collective action (...), to compel a service provider of another member state to subscribe to the rate of pay determined in accordance with a collective agreement which is applicable in practice to domestic undertakings in the same sector".
In the Viking case, Advocate-General Miguel Poiares Maduro expressed the view that trade unions could take collective action to dissuade a company from relocating within the community, as long as this did not partition the labour market along national lines or prevent a relocated company from providing services in another member state.
He argued: "Article 43 EC does not preclude a trade union or an association of trade unions from taking collective action which has the effect of restricting the right of establishment of an undertaking that intends to relocate to another member state, in order to protect the workers of that undertaking. It is for the national court to determine whether such action is lawful in the light of the applicable domestic rules regarding the exercise of the right to collective action, provided that cases of intra-Community relocation are not treated less favourably than cases of relocation within the national borders."
