The European Union’s Legal System and Domestic Policy: Spillover or Backlash?

The legal system of the European Union (EU) offers domestic actors a powerful tool to influence national policy. European law can be drawn on by private litigants in national courts to challenge national policies. These challenges can be sent by national judges to the European Court of Justice (ECJ), which instructs national courts to apply European law instead of national law, or to interpret national law in a way compatible with European law. Combining victories in front of the ECJ with political mobilization and pressure, litigants and groups have used the European legal system to force their governments to change national policies. Using Europe’s legal tool involves overcoming four successive thresholds: First, there must be a point of European law on which domestic actors can draw and favorable ECJ interpretations of this law. Second, litigants must embrace EU law to advance their policy objectives, using EU legal arguments in national court cases. Third, national courts must support the efforts of the litigants by referring cases to the ECJ and/or applying the ECJ’s legal interpretations instead of conflicting national policy. Fourth, litigants must follow through on their legal victory, using it as part of a larger strategy to pressure the government to change public policy.1 A litigation strategy can fail at any of the four steps. When private litigants can surmount these four thresholds, the EU legal system can be a potent tool for forcing a change in national policy. Stated as such, these four steps may sound onerous. But litigants have used this tool successfully many times. In one of the most well-known examples, equal opportunity groups used the EU legal system to force a Conservative British government to make considerable reforms to British equality policy at the height of British antagonism toward the EU and EU social policy.2