A voter roll, also known as an electoral roll or voter registration list, is a compilation that lists persons who are entitled to vote for particular elections in a particular jurisdiction. The list is usually broken down by electoral districts and is primarily prepared to assist election officials at polling places. Most jurisdictions maintain permanent electoral rolls, which are updated continuously or periodically, while some jurisdictions compile new electoral rolls before each election. Voter registration can be used to detect electoral fraud by enabling authorities to verify an applicants identity and entitlement to a vote, and to ensure a person doesnt vote multiple times. In jurisdictions where voting is compulsory, the electoral roll is used to indicate who has failed to vote. Voter rolls are constantly changing as new voters register and existing registrants move, change their name, pass away, or otherwise become ineligible. Because of the importance of these lists, states are required to keep voter registration rolls as accurate and up-to-date as possible. This is called voter roll list maintenance or cleaning the voter rolls. Voter rolls are maintained by local and state governments.