384. Most electoral challenges originate directly or indirectly from an action, decision or omission by the EMB. The role of the EMB is thus especially important in carrying out the judgements or decisions, and electoral legislation must establish a duty of the EMB to assist EDRBs and allow full access for interested parties and candidates to the relevant EMB materials and files. It is therefore desirable that collaborative relations exist between the EDRB and the EMB, quite independent of the possibility of the EDRB imposing a measure that requires the EMB to act or lodging a complaint so that some type of liability can be attributed to the EMB. g) Consistency in the interpretation and application of the electoral laws 385. One sign of the independence and impartiality of an EDRB is its consistency in the interpretation and application of the constitutional, statutory, regulatory and, where applicable, international provisions pertaining to elections, regardless of the political pressures and any other circumstances or actors involved. When dynamic and changing circumstances or new insights into the provisions applicable by the EDRB appear to demand a change in interpretation, special care should be taken to justify such changes fully and to ensure that they are truly exceptional. The predictability of the actions of EDRBs is fundamental to legal certainty and the credibility of the EDR system. Any change easily triggers suspicions of political bias. 386. In EDR systems that are entrusted to regular courts that are part of the judicial branch and are part of the common law tradition (for example Australia, Canada, India and the UK), under the doctrine of stare decisis an interpretation of the law previously embraced by a court becomes binding precedent for the same judicial body in future cases. Only by deciding that a later case is different can a court stray from a certain standard of interpretation previously upheld. It must conclude that the new case contains characteristics that are substantially different to make the precedent inapplicable. 131 6. Principles and guarantees of EDR systems out the judgements or rulings that result from electoral challenges. In addition, the sanctions of suspension or cancellation of the registration of political parties or candidates are vulnerable to abuse. The EDRB must act firmly and prudently to ensure the full enforcement of its judgements and rulings. However, it should consider refraining from ordering certain actions to be carried out by a person with respect to whom it does not have any mechanisms to ensure compliance. It is often preferable to recognize the lack of legal mechanisms to bind and order someone to engage in certain conduct rather than order it and then have the order ignored. The credibility of an EDRB would be seriously impaired if it were to hand down judgements or rulings that were ignored by those to whom they were directed. However, such situations would be likely to provide evidence of a need for reform of legislation.