As a result, several member states have had to pay significant fines for violation of compliance with different provisions of the ND. The jurisprudence helped explain the requirements of the ND, thereby extending common rules. Furthermore, these legal actions and other implementation initiatives by national Courts of Auditors have triggered policy responses, encouraging stricter enforcement of Nitrate Action Plans, but they did not result in an effective incentive for farmers to change practices. This led to the adoption of a series of Action Plans that focused on non-point pollution, mainly from nitrogen and phosphorus applied in agriculture.