Lobbyists before the US Supreme Court - Investigating the influence of amicus curiae briefs

Despite the fact that amicus curiae participation is the most common method of interest group activity in the judicial arena, there is little consensus as to whether this means of participation influences the decision making of the U.S. Supreme Court. To redress this state of affairs, this research investigates the affect of amicus briefs on the ideological direction of the Court's decisions, with particular attention given to theoretical and methodological issues that have gone unexplored in previous studies. Analyzing group influence during the 1946 to 1995 terms, the results provide particularly robust evidence that pressure groups are effective in shaping the Court's policy outputs. These findings therefore indicate that elite decision makers can be influenced by persuasive argumentation presented by organized interests.