The by-election is an election held to fill the vacancy in a constituency in the case of any candidate who resigns or dies before the expiration of his period of office. Generally, a By-election is conducted when any member of the parliament has died or has become incompetent to hold the office acquired by him. By-elections are also conducted due to voting irregularities.
In the context of Nepal, a By-election is conducted when an elected candidate dies or becomes incompetent to hold office. By-election is conducted for federal parliament, state assembly, or local level but there is no By-election is conducted if the period of holding office by the candidate is less than six months.
If a seat becomes vacant between elections, List PR systems often simply fill the seat with the next candidate on the list of the party of the former representative, eliminating the need to hold another election. Plurality/Majority systems are likely to have provisions to fill a vacant seat through a by-election.
When other systems are in use, either approach may be possible: the Republic of Ireland holds by-elections for vacant seats in the legislature, but Australia does not do so for Senate vacancies.
By-elections are cheaper because they are smaller than regular elections, but some countries still have a large budget burden and cannot hold by-elections, leaving seats vacant for extended periods. By-elections can serve as an interim test of government effectiveness in some circumstances.
Read Also: What is election law?