The central purpose of this paper is to discover the impact of the European Parliament (EP) on the European Union’s social policy and also to identify the conditions that explain the degree and direction of its influence. Hypotheses gathered from the literature are: the influence of the EP depends on the type of policy (i), the EP’s influence depends on the relevance of the amendment (ii), the EP is the main promoter of diffuse interests (iii), the position of the EP should be mainly on the left-right dimension (iv), and the position of the EP should only be on the European integration dimension (v). A content analysis is the main part of this paper. It is conducted of all the positions of the EP in the first reading on all social political legislative processes in the period from 1986-2010 under the cooperation or the co-decision procedure that got an ‘approval with amendments’. The purpose of this analysis is to find the substantive influence of the EP during the legislative process and to find how the EP changes the different proposals. In the content analysis every amendment is coded in seven different dimensions: influence, relevance, social policy, type of interest, European integration, empowerment, and formal amendments. The first result of this analysis is that most of the EP’s amendments are relevant. The second finding is that the EP has more influence under the co-decision procedure than under the cooperation one. The increase of diffuse interest promotion of the EP is another interesting finding. This is particularly true for gender equality. Fourthly, the EP tries to transfer more competence to the European level, but it is only rarely successful. The final remarkable result is that the EP promoted more extensive social political standards at the European level from the late 1980s onwards.
