After the law is passed in the Bundestag, it goes to the Bundesrat, which represents the federal states.

The Bundesrat checks whether the interests of the states and the constitution have been respected.

For laws affecting the states, the Bundesrat has a right of approval (approval laws). For others, it can only raise objections (objection laws).

In the case of the environmental protection law: If the Bundesrat has concerns, it can call for a mediation committee. After agreement, the law can be finally passed.