Faced with uncertainty regarding a law's effects on fundamental rights, the Federal Constitutional Court of Germany has developed original case law as part of the constitutionality review of legislation by imposing an obligation of legislative monitoring and correction in such cases. Concretely, the Constitutional Court forces the legislator to systematically gather the necessary data and use it to evaluate the effects of legislation and to correct that legislation based on the evaluation. Rather than prohibiting the activity or the new legislation, the judge applies formal conditions. The Federal Supreme Court of Switzerland has applied the same principle on some occasions. In this context, the law undergoes a maturation process. It adapts to a changing environment, no longer claiming to provide a permanent solution. The legislator's duty no longer ends when a law is enacted – rather, enactment becomes a prelude.