The Contextual Dependence of Movement Outcomes: A Simplified Meta-Analysis

This article investigates the empirical evidence for the statement that the impact of social movement organizations (SMOs) and interest groups on policy making is dependent on public opinion and the political system. A meta-analysis of articles published in eleven sociology and political science journals from 1990 to 2007 is used to test two hypotheses: 1) when public opinion is taken into account, SMOs and interest groups have no direct effect on policy; 2) the existence of a democratic regime is a necessary precondition for finding any policy impact of SMOs and interest groups. Results show that taking account of public opinion does not generally make any difference in the finding of direct effects. However, the role of public opinion varies across the measures of organizational resources and activity. I also find that a democratic regime is not a necessary precondition for the impact of SMOs and interest groups on public policy, but show that a direct effect of interest organizations is less likely to be found in the studies that take account of political regime.