While the cancellation of election results must in principle be grounded on violation of law, it must be borne in mind that constitutional courts may have the competence to assess the constitutionality of electoral legislation when dealing with electoral disputes. Consequently, constitutional courts may also have the power to invalidate elections after having found that the legislation does not guarantee the right to free elections as required by the ECHR and the national Constitution, including in case the law fails to regulate important aspects of election campaigning and the main elements of elections.